Receptor that binds IL-17

ABSTRACT

Isolated receptors for IL-17, DNA&#39;s encoding such receptors, and pharmaceutical compositions made therefrom, are disclosed. The isolated receptors can be used to regulate an immune response.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. application Ser. No.08/538,765, filed Aug. 7, 1995, now abandoned, which is acontinuation-in-part of U.S. application Ser. No. 08/410,535, filed Mar.23, 1995, now abandoned.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to the field of cytokinereceptors, and more specifically to cytokine receptor proteins havingimmunoregulatory activity.

BACKGROUND OF THE INVENTION

Cytokines are hormone-like molecules that regulate various aspects of animmune or inflammatory response. Cytokines exert their effects byspecifically binding receptors present on cells, and transducing asignal to the cells. Rouvier et al. (J. Immunol. 150:5445; 1993)reported a novel cDNA which they termed CTLA-8. The putative CTLA8protein is 57% homologous to the predicted amino acid sequence of anopen reading frame (ORF) present in Herpesvirus saimiri (HSV) referredto as HVS13 (Nicholas et al. Virol. 179:1 89, 1990; Albrecht et al., J.Virol. 66:5047;1992). However, the function, if any of either CTLA-8 orHVS13 was not known, nor was a receptor or binding protein for CTLA-8 orHVS13 known. Thus, prior to the present invention, there was a need inthe art to determine the function of CTLA-8 and HVS13, and to identifyreceptor molecules or binding proteins that play a role in the functionof these proteins.

SUMMARY OF THE INVENTION

The present invention identifies a novel receptor that binds IL-17(CTLA-8) and HVS13, a viral homolog of IL-17; DNAs encoding the novelreceptor and novel receptor proteins are provided. The receptor is aType I transmembrane protein; the mouse receptor has 864 amino acidresidues, the human receptor has 866 amino acid residues. Soluble formsof the receptor can be prepared and used to regulate immune responses ina therapeutic setting; accordingly, pharmaceutical compositionscomprising soluble forms of the novel receptor are also provided.Deleted forms and fusion proteins comprising the novel receptor, andhomologs thereof are also disclosed. Also provided are methods ofregulating an immune response, and methods of suppressing rejection ofgrafted organs or tissue. These and other aspects of the presentinvention will become evident upon reference to the following detaileddescription of the invention.

DETAILED DESCRIPTION OF THE INVENTION

A soluble IL-17 (CTLA-8) protein and an ORF present in Herpesvirussaimiri (HVS13) were expressed as fusion proteins comprising animmunoglobulin Fc region, and used to screen cells for expression of areceptor for IL-17. T cell thymoma EL4 cells were found to bind theHVS13/Fc as well as murine CTLA8 (IL-17)/Fc fusion protein. A cDNAlibrary from EL4 cells was prepared and screened for expression of thereceptor. The receptor is a Type I transmembrane protein with 864 aminoacid residues, which is referred to as IL-17R (CTLA-8R). Various formsof IL-17R were prepared, including IL-17R/Fc protein, a soluble IL-17Rwhich contains the signal peptide and extracellular domain of IL-17R,and a soluble IL-17R/Flag® construct. A human IL-17R was isolated from ahuman peripheral blood lymphocyte library by cross-specieshybridization, and exhibits similarities to the murine IL-17R.

IL-17, HVS13 and homologous proteins

CTLA-8 refers to a cDNA cloned from an activated T cell hybridoma clone(Rouvier et al., J. Immunol. 150:5445; 1993). Northern blot analysisindicated that CTLA-8 transcription was very tissue specific. The CTLA-8gene was found to map at chromosomal site 1a in mice, and at 2q31 inhumans. Although a protein encoded by the CTLA-8 gene was neveridentified by Rouvier et al, the predicted amino acid sequence of CTLA-8was found to be 57% homologous to the predicted amino acid sequence ofan ORF present in Herpesvirus Saimiri, HVS13. The CTLA-8 protein isreferred to herein as Interleukin-17 (IL-17).

The complete nucleotide sequence of the genome of HVS has been reported(Albrecht et al., J. Virol. 66:5047; 1992). Additional studies on one ofthe HVS open reading frames (ORFs), HVS13, are described in Nicholas etal., Virol. 179:1 89; 1990. HVS13 is a late gene which is present in theHind III-G fragment of HVS. Antisera developed against peptides derivedfrom HVS13 are believed to react with a late protein (Nicholas et al.,supra).

As described U.S. Ser. No. 08/462,353, now abandoned, a CIP of U.S. Ser.No. 08/410,536, filed Mar. 23, 1995, now abandoned, full length murineCTLA-8 protein and a CTLA-8/Fc fusion protein were expressed, tested,and found to act as a costimulus for the proliferation of T cells. HumanIL-17 (CTLA-8) was identified by probing a human T cell library using aDNA fragment derived from degenerate PCR; homologs of IL-17 (CTLA-8) areexpected to exist in other species as well. A full length HVS13 protein,as well as an HVS13/Fc fusion protein, were also expressed, and found toact in a similar manner to IL-17 (CTLA-8) protein. Moreover, otherspecies of herpesviruses are also likely to encode proteins homologousto that encoded by HVS13.

Proteins and Analogs

The present invention provides isolated IL-17R and homologs thereofhaving immunoregulatory activity. Such proteins are substantially freeof contaminating endogenous materials and, optionally, withoutassociated native-pattern glycosylation. Derivatives of IL-17R withinthe scope of the invention also include various structural forms of theprimary protein which retain biological activity. Due to the presence ofionizable amino and carboxyl groups, for example, an IL-17R protein maybe in the form of acidic or basic salts, or may be in neutral form.Individual amino acid residues may also be modified by oxidation orreduction.

The primary amino acid structure may be modified by forming covalent oraggregative conjugates with other chemical moieties, such as glycosylgroups, lipids, phosphate, acetyl groups and the like, or by creatingamino acid sequence mutants. Covalent derivatives are prepared bylinking particular functional groups to amino acid side chains or at theN- or C-termini.

Soluble forms of IL-17R are also within the scope of the invention. Thenucleotide and predicted amino acid sequence of the murine IL-17R isshown in SEQ ID NOs:1 and 2. Computer analysis indicated that theprotein has an N-terminal signal peptide with a cleavage site betweenamino acid 31 and 32. Those skilled in the art will recognize that theactual cleavage site may be different than that predicted by computeranalysis. Thus, the N-terminal amino acid of the cleaved peptide isexpected to be within about five amino acids on either side of thepredicted cleavage site. The signal peptide is followed by a 291 aminoacid extracellular domain, a 21 amino acid transmembrane domain, and a521 amino acid cytoplasmic tail. Soluble IL-17R comprises the signalpeptide and the extracellular domain (residues 1 to 322 of SEQ ID NO:1)or a fragment thereof. Alternatively, a different signal peptide can besubstituted for residues 1 through 31 of SEQ ID NO:1.

The nucleotide and predicted amino acid sequence of the human IL-17R isshown in SEQ ID NOs:9 and 10. It shares many features with the murineIL-17 R. Computer analysis indicated that the protein has an N-terminalsignal peptide with a cleavage site between amino acid 27 and 28. Thoseskilled in the art will recognize that the actual cleavage site may bedifferent than that predicted by computer analysis. Thus, the N-terminalamino acid of the cleaved peptide is expected to be within about fiveamino acids on either side of the predicted cleavage site. The signalpeptide is followed by a 293 amino acid extracellular domain, a 21 aminoacid transmembrane domain, and a 525 amino acid cytoplasmic tail.Soluble IL-17R comprises the signal peptide and the extracellular domain(residues 1 to 320 of SEQ ID NO:1) or a fragment thereof. Alternatively,a different signal peptide can be substituted for the native signalpeptide.

Other derivatives of the IL-17R protein and homologs thereof within thescope of this invention include covalent or aggregative conjugates ofthe protein or its fragments with other proteins or polypeptides, suchas by synthesis in recombinant culture as N-terminal or C-terminalfusions. For example, the conjugated peptide may be a signal (or leader)polypeptide sequence at the N-terminal region of the protein whichco-translationally or post-translationally directs transfer of theprotein from its site of synthesis to its site of function inside oroutside of the cell membrane or wall (e.g., the yeast α-factor leader).

Protein fusions can comprise peptides added to facilitate purificationor identification of IL-17R proteins and homologs (e.g., poly-His). Theamino acid sequence of the inventive proteins can also be linked to anidentification peptide such as that described by Hopp et al.,Bio/Technology 6:1204 (1988). Such a highly antigenic peptide providesan epitope reversibly bound by a specific monoclonal antibody, enablingrapid assay and facile purification of expressed recombinant protein.The sequence of Hopp et al. is also specifically cleaved by bovinemucosal enterokinase, allowing removal of the peptide from the purifiedprotein. Fusion proteins capped with such peptides may also be resistantto intracellular degradation in E. coli.

Fusion proteins further comprise the amino acid sequence of a IL-17Rlinked to an immunoglobulin Fc region. An exemplary Fc region is a humanIgG1 having a nucleotide and amino acid sequence set forth in SEQ IDNO:4. Fragments of an Fc region may also be used, as can Fc muteins suchas those described in U.S. Ser. No. 08/145,830, filed Oct. 29, 1993.Depending on the portion of the Fc region used, a fusion protein may beexpressed as a dimer, through formation of interchain disulfide bonds.If the fusion proteins are made with both heavy and light chains of anantibody, it is possible to form a protein oligomer with as many as fourIL-17R regions.

In another embodiment, IL-17R and homologs thereof further comprise anoligomerizing zipper domain. Zipper domains are described in U.S. Ser.No. 08/107,353, filed Aug. 13, 1993, the relevant disclosure of which isincorporated by reference herein. Examples of leucine zipper domains arethose found in the yeast transcription factor GCN4 and a heat-stableDNA-binding protein found in rat liver (C/EBP; Landschulz et al.,Science 243:1681, 1989), the nuclear transforming proteins, fos and jun,which preferentially form a heterodimer (O'Shea et al., Science 245:646,1989; Turner and Tjian, Science 243:1689, 1989), and the gene product ofthe murine proto-oncogene, c-myc (Landschulz et al., Science 240:1759,1988). The fusogenic proteins of several different includingparamyxovirus, coronavirus, measles virus and many retroviruses, alsopossess leucine zipper domains (Buckland and Wild, Nature 338:547, 1989;Britton, Nature 353:394, 1991; Delwart and Mosialos, AIDS Research andHuman Retroviruses 6:703, 1990).

Derivatives of IL-17R may also be used as immunogens, reagents in invitro assays, or as binding agents for affinity purification procedures.Such derivatives may also be obtained by cross-linking agents, such asM-maleimidobenzoyl succinimide ester and N-hydroxysuccinimide, atcysteine and lysine residues. The inventive proteins may also becovalently bound through reactive side groups to various insolublesubstrates, such as cyanogen bromide-activated, bisoxirane-activated,carbonyldiimidazole-activated or tosyl-activated agarose structures, orby adsorbing to polyolefin surfaces (with or without glutaraldehydecross-linking). Once bound to a substrate, proteins may be used toselectively bind (for purposes of assay or purification) antibodiesraised against the IL-17R or against other proteins which are similar tothe IL-17R, as well as other proteins that bind IL-17R or its homologousproteins.

The present invention also includes IL-17R with or without associatednative-pattern glycosylation. Proteins expressed in yeast or mammalianexpression systems, e.g., COS-7 cells, may be similar or slightlydifferent in molecular weight and glycosylation pattern than the nativemolecules, depending upon the expression system. Expression of DNAsencoding the inventive proteins in bacteria such as E. coli providesnon-glycosylated molecules. Functional mutant analogs of IL-17R proteinor homologs thereof having inactivated N-glycosylation sites can beproduced by oligonucleotide synthesis and ligation or by site-specificmutagenesis techniques. These analog proteins can be produced in ahomogeneous, reduced-carbohydrate form in good yield using yeastexpression systems. N-glycosylation sites in eukaryotic proteins arecharacterized by the amino acid triplet Asn- A₁ -Z, where A₁ is anyamino acid except Pro, and Z is Ser or Thr. In this sequence, asparagineprovides a side chain amino group for covalent attachment ofcarbohydrate. Such a site can be eliminated by substituting anotheramino acid for Asn or for residue Z, deleting Asn or Z, or inserting anon-Z amino acid between A₁ and Z, or an amino acid other than Asnbetween Asn and A1₁.

IL-17R protein derivatives may also be obtained by mutations of thenative IL-17R or its subunits. A IL-17R mutated protein, as referred toherein, is a polypeptide homologous to a IL-17R protein but which has anamino acid sequence different from the native IL-17R because of one or aplurality of deletions, insertions or substitutions. The effect of anymutation made in a DNA encoding a IL-17R peptide may be easilydetermined by analyzing the ability of the mutated IL-17R peptide toinhibit costimulation of T or B cells by IL-17 (CTLA-8) or homologousproteins, or to bind proteins that specifically bind IL-17R (forexample, antibodies or proteins encoded by the CTLA-8 cDNA or the HVS13ORF). Moreover, activity of IL-17R analogs, muteins or derivatives canbe determined by any of the assays methods described herein. Similarmutations may be made in homologs of IL-17R, and tested in a similarmanner.

Bioequivalent analogs of the inventive proteins may be constructed by,for example, making various substitutions of residues or sequences ordeleting terminal or internal residues or sequences not needed forbiological activity. For example, cysteine residues can be deleted orreplaced with other amino acids to prevent formation of incorrectintramolecular disulfide bridges upon renaturation. Other approaches tomutagenesis involve modification of adjacent dibasic amino acid residuesto enhance expression in yeast systems in which KEX2 protease activityis present.

Generally, substitutions should be made conservatively; i.e., the mostpreferred substitute amino acids are those which do not affect theability of the inventive proteins to bind their ligands in a mannersubstantially equivalent to that of native mIL-17R or hIL-17R. Examplesof conservative substitutions include substitution of amino acidsoutside of the binding domain(s), and substitution of amino acids thatdo not alter the secondary and/or tertiary structure of IL-17R andhomologs thereof. Additional examples include substituting one aliphaticresidue for another, such as Ile, Val, Leu, or Ala for one another, orsubstitutions of one polar residue for another, such as between Lys andArg; Glu and Asp; or Gln and Asn. Other such conservative substitutions,for example, substitutions of entire regions having similarhydrophobicity characteristics, are well known.

Similarly, when a deletion or insertion strategy is adopted, thepotential effect of the deletion or insertion on biological activityshould be considered. Subunits of the inventive proteins may beconstructed by deleting terminal or internal residues or sequences.Fragments of IL-17R that bind IL-17 can be readily prepared (forexample, by using restriction enzymes to delete portions of the DNA) andtested for their ability to bind IL-17. Additional guidance as to thetypes of mutations that can be made is provided by a comparison of thesequence of IL-17R to proteins that have similar structures, as well asby performing structural analysis of the inventive proteins.

Mutations in nucleotide sequences constructed for expression of analogIL-17R CTLA-8R) must, of course, preserve the reading frame phase of thecoding sequences and preferably will not create complementary regionsthat could hybridize to produce secondary mRNA structures such as loopsor hairpins which would adversely affect translation of the receptormRNA. Although a mutation site may be predetermined, it is not necessarythat the nature of the mutation per se be predetermined. For example, inorder to select for optimum characteristics of mutants at a given site,random mutagenesis may be conducted at the target codon and theexpressed mutated viral proteins screened for the desired activity.

Not all mutations in the nucleotide sequence which encodes a IL-17Rprotein or homolog thereof will be expressed in the final product, forexample, nucleotide substitutions may be made to enhance expression,primarily to avoid secondary structure loops in the transcribed MRNA(see EPA 75,444A, incorporated herein by reference), or to providecodons that are more readily translated by the selected host, e.g., thewell-known E. coli preference codons for E. coli expression.

Mutations can be introduced at particular loci by synthesizingoligonucleotides containing a mutant sequence, flanked by restrictionsites enabling ligation to fragments of the native sequence. Followingligation, the resulting reconstructed sequence encodes an analog havingthe desired amino acid insertion, substitution, or deletion.

Alternatively, oligonucleotide-directed site-specific mutagenesisprocedures can be employed to provide an altered gene having particularcodons altered according to the substitution, deletion, or insertionrequired. Exemplary methods of making the alterations set forth aboveare disclosed by Walder et al. (Gene 42:133, 1986); Bauer et al. (Gene37:73, 1985); Craik (BioTechniques, Jan. 1985, 12-19); Smith et al.(Genetic Engineering: Principles and Methods, Plenum Press, 1981); andU.S. Pat. Nos. 4,518,584 and 4,737,462 disclose suitable techniques, andare incorporated by reference herein.

Due to code degeneracy, there can be considerable variation innucleotide sequences encoding the same amino acid sequence. Otherembodiments include sequences capable of hybridizing under moderatelystringent conditions (prewashing solution of 5×SSC, 0.5% SDS, 1.0 mMEDTA (pH 8.0) and hybridization conditions of 50° C., 5×SSC, overnight)to the DNA sequences encoding IL-17R, and other sequences which aredegenerate to those which encode the IL-17R. In a preferred embodiment,IL-17R analogs are at least about 70% identical in amino acid sequenceto the amino acid sequence of IL-17R proteins as set forth in SEQ IDNO:1 or SEQ ID NO:9. Similarly, analogs of IL-17R homologs are at leastabout 70% identical in amino acid sequence to the amino acid sequence ofthe native, homologous proteins. In a most preferred embodiment, analogsof IL-17R or homologs thereof are at least about 80% identical in aminoacid sequence to the native form of the inventive proteins.

Percent identity may be determined using a computer program, forexample, the GAP computer program described by Devereux et al. (NucL.Acids Res. 12:387, 1984) and available from the University of WisconsinGenetics Computer Group (UWGCG). For fragments derived from the IL-17Rprotein, the identity is calculated based on that portion of the IL-17Rprotein that is present in the fragment. Similar methods can be used toanalyze homologs of IL-17R.

The ability of IL-17R analogs to bind CTLA-8 can be determined bytesting the ability of the analogs to inhibit IL-17 (CTLA-8)-induced Tcell proliferation. Alternatively, suitable assays, for example, anenzyme immunoassay or a dot blot, employing CTLA-8 or HSV13 (or ahomolog thereof which binds native IL-17R) can be used to assess theability of IL-17R analogs to bind CTLA-8. Such methods are well known inthe art.

The IL-17R proteins and analogs described herein will have numeroususes, including the preparation of pharmaceutical compositions. Theinventive proteins will also be useful in preparing kits that are usedto detect IL-17 or IL-17R, for example, in patient specimens. Such kitswill also find uses in detecting the interaction of IL-17 and IL-17R, asis necessary when screening for antagonists or mimetics of thisinteraction (for example, peptides or small molecules that inhibit ormimic, respectively, the interaction). A variety of assay formats areuseful in such kits, including (but not limited to) ELISA, dot blot,solid phase binding assays (such as those using a biosensor), rapidformat assays and bioassays.

Expression of Recombinant Receptors for IL-17

The proteins of the present invention are preferably produced byrecombinant DNA methods by inserting a DNA sequence encoding IL-17Rprotein or a homolog thereof into a recombinant expression vector andexpressing the DNA sequence in a recombinant microbial expression systemunder conditions promoting expression. DNA sequences encoding theproteins provided by this invention can be assembled from cDNA fragmentsand short oligonucleotide linkers, or from a series of oligonucleotides,to provide a synthetic gene which is capable of being inserted in arecombinant expression vector and expressed in a recombinanttranscriptional unit.

Recombinant expression vectors include synthetic or cDNA-derived DNAfragments encoding IL-17R, homologs, or bioequivalent analogs, operablylinked to suitable transcriptional or translational regulatory elementsderived from mammalian, microbial, viral or insect genes. Suchregulatory elements include a transcriptional promoter, an optionaloperator sequence to control transcription, a sequence encoding suitableMRNA ribosomal binding sites, and sequences which control thetermination of transcription and translation, as described in detailbelow. The ability to replicate in a host, usually conferred by anorigin of replication, and a selection gene to facilitate recognition oftransformants may additionally be incorporated.

DNA regions are operably linked when they are functionally related toeach other. For example, DNA for a signal peptide (secretory leader) isoperably linked to DNA for a polypeptide if it is expressed as aprecursor which participates in the secretion of the polypeptide; apromoter is operably linked to a coding sequence if it controls thetranscription of the sequence; or a ribosome binding site is operablylinked to a coding sequence if it is positioned so as to permittranslation. Generally, operably linked means contiguous and, in thecase of secretory leaders, contiguous and in reading frame. DNAsequences encoding IL-17R or homologs which are to be expressed in amicroorganism will preferably contain no introns that could prematurelyterminate transcription of DNA into mRNA.

Useful expression vectors for bacterial use can comprise a selectablemarker and bacterial origin of replication derived from commerciallyavailable plasmids comprising genetic elements of the well known cloningvector pBR322 (ATCC 37017). Such commercial vectors include, forexample, pKK223-3 (Pharmacia Fine Chemicals, Uppsala, Sweden) and pGEM1(Promega Biotec, Madison, Wis., USA). These pBR322 "backbone" sectionsare combined with an appropriate promoter and the structural sequence tobe expressed. E. coli is typically transformed using derivatives ofpBR322, a plasmid derived from an E. coli species (Bolivar et al., Gene2:95, 1977). pBR322 contains genes for ampicillin and tetracyclineresistance and thus provides simple means for identifying transformedcells.

Promoters commonly used in recombinant microbial expression vectorsinclude the β-lactamase (penicillinase) and lactose promoter system(Chang et al., Nature 275:615, 1978; and Goeddel et al., Nature 281:544,1979), the tryptophan (trp) promoter system (Goeddel et al., Nucl. AcidsRes. 8:4057, 1980; and EPA 36,776) and tac promoter (Maniatis, MolecularCloning: A Laboratory Manual, Cold Spring Harbor Laboratory, p. 412,1982). A particularly useful bacterial expression system employs thephage λP_(L) promoter and cI857ts thermolabile repressor. Plasmidvectors available from the American Type Culture Collection whichincorporate derivatives of the λP_(L) promoter include plasmid pHUB2,resident in E. coli strain JMB9 (ATCC 37092) and pPLc28, resident in E.coli RR1 (ATCC 53082).

Suitable promoter sequences in yeast vectors include the promoters formetallothionein, 3-phosphoglycerate kinase (Hitzeman et al., J. Biol.Chem. 255:2073, 1980) or other glycolytic enzymes (Hess et al., J. Adv.Enzyme Reg. 7:149, 1968; and Holland et al., Biochem. 17:4900, 1978),such as enolase, glyceraldehyde-3-phosphate dehydrogenase, hexokinase,pyruvate decarboxylase, phosphofructokinase, glucose-6-phosphateisomerase, 3-phosphoglycerate mutase, pyruvate kinase, triosephosphateisomerase, phosphoglucose isomerase, and glucokinase. Suitable vectorsand promoters for use in yeast expression are further described in R.Hitzeman et al., EPA 73,657.

Preferred yeast vectors can be assembled using DNA sequences from pBR322for selection and replication in E. coli (Amp^(r) gene and origin ofreplication) and yeast DNA sequences including a glucose-repressibleADH2 promoter and α-factor secretion leader. The ADH2 promoter has beendescribed by Russell et al. (J. Biol. Chem. 258:2674, 1982) and Beier etal. (Nature 300:724, 1982). The yeast α-factor leader, which directssecretion of heterologous proteins, can be inserted between the promoterand the structural gene to be expressed. See, e.g., Kurjan et al., Cell30:933, 1982; and Bitter et al., Proc. Natl. Acad. Sci. USA 81:5330,1984. The leader sequence may be modified to contain, near its 3' end,one or more useful restriction sites to facilitate fusion of the leadersequence to foreign genes.

The transcriptional and translational control sequences in expressionvectors to be used in transforming vertebrate cells may be provided byviral sources. For example, commonly used promoters and enhancers arederived from Polyoma, Adenovirus 2, Simian Virus 40 (SV40), and humancytomegalovirus. DNA sequences derived from the SV40 viral genome, forexample, SV40 origin, early and late promoter, enhancer, splice, andpolyadenylation sites may be used to provide the other genetic elementsrequired for expression of a heterologous DNA sequence. The early andlate promoters are particularly useful because both are obtained easilyfrom the virus as a fragment which also contains the SV40 viral originof replication (Fiers et al., Nature 273:113, 1978). Smaller or largerSV40 fragments may also be used, provided the approximately 250 bpsequence extending from the Hind III site toward the BglI site locatedin the viral origin of replication is included. Further, viral genomicpromoter, control and/or signal sequences may be utilized, provided suchcontrol sequences are compatible with the host cell chosen. Exemplaryvectors can be constructed as disclosed by Okayama and Berg (Mol. Cell.Biol. 3:280, 1983).

A useful system for stable high level expression of mammalian receptorcDNAs in C127 murine mammary epithelial cells can be constructedsubstantially as described by Cosman et al. (Mol. Immunol. 23:935,1986). A preferred eukaryotic vector for expression of IL-17R DNA isreferred to as pDC406 (McMahan et al., EMBO J. 10:2821, 1991), andincludes regulatory sequences derived from SV40, human immunodeficiencyvirus (HIV), and Epstein-Barr virus (EBV). Other preferred vectorsinclude pDC409 and pDC410, which are derived from pDC406. pDC410 wasderived from pDC406 by substituting the EBV origin of replication withsequences encoding the SV40 large T antigen. pDC409 differs from pDC406in that a Bgl II restriction site outside of the multiple cloning sitehas been deleted, making the Bgl II site within the multiple cloningsite unique.

A useful cell line that allows for episomal replication of expressionvectors, such as pDC406 and pDC409, which contain the EBV origin ofreplication, is CV-1/EBNA (ATCC CRL 10478). The CV-1/EBNA cell line wasderived by transfection of the CV-1 cell line with a gene encodingEpstein-Barr virus nuclear antigen-1 (EBNA-1) and constitutively expressEBNA-1 driven from human CMV immediate-early enhancer/promoter.

Host Cells

Transformed host cells are cells which have been transformed ortransfected with expression vectors constructed using recombinant DNAtechniques and which contain sequences encoding the proteins of thepresent invention. Transformed host cells may express the desiredprotein (IL-17R or homologs thereof), but host cells transformed forpurposes of cloning or amplifying the inventive DNA do not need toexpress the protein. Expressed proteins will preferably be secreted intothe culture supernatant, depending on the DNA selected, but may bedeposited in the cell membrane.

Suitable host cells for expression of viral proteins includeprokaryotes, yeast or higher eukaryotic cells under the control ofappropriate promoters. Prokaryotes include gram negative or grampositive organisms, for example E. coli or Bacillus spp. Highereukaryotic cells include established cell lines of mammalian origin asdescribed below. Cell-free translation systems could also be employed toproduce viral proteins using RNAs derived from the DNA constructsdisclosed herein. Appropriate cloning and expression vectors for usewith bacterial, fungal, yeast, and mammalian cellular hosts aredescribed by Pouwels et al. (Cloning Vectors: A Laboratory Manual,Elsevier, N.Y., 1985), the relevant disclosure of which is herebyincorporated by reference.

Prokaryotic expression hosts may be used for expression of IL-17R orhomologs that do not require extensive proteolytic and disulfideprocessing. Prokaryotic expression vectors generally comprise one ormore phenotypic selectable markers, for example a gene encoding proteinsconferring antibiotic resistance or supplying an autotrophicrequirement, and an origin of replication recognized by the host toensure amplification within the host. Suitable prokaryotic hosts fortransformation include E. coli, Bacillus subtilis, Salmonellatyphimurium, and various species within the genera Pseudomonas,Streptomyces, and Staphylococcus, although others may also be employedas a matter of choice.

Recombinant IL-17R may also be expressed in yeast hosts, preferably fromthe Saccharomyces species, such as S. cerevisiae. Yeast of other genera,such as Pichia or Kluyveromyces may also be employed. Yeast vectors willgenerally contain an origin of replication from the 2μ yeast plasmid oran autonomously replicating sequence (ARS), promoter, DNA encoding theviral protein, sequences for polyadenylation and transcriptiontermination and a selection gene. Preferably, yeast vectors will includean origin of replication and selectable marker permitting transformationof both yeast and E. coli, e.g., the ampicillin resistance gene of E.coli and S. cerevisiae trp1 gene, which provides a selection marker fora mutant strain of yeast lacking the ability to grow in tryptophan, anda promoter derived from a highly expressed yeast gene to inducetranscription of a structural sequence downstream. The presence of thetrp1 lesion in the yeast host cell genome then provides an effectiveenvironment for detecting transformation by growth in the absence oftryptophan.

Suitable yeast transformation protocols are known to those of skill inthe art; an exemplary technique is described by Hinnen et al., Proc.Natl. Acad. Sci. USA 75:1929, 1978, selecting for Trp⁺ transformants ina selective medium consisting of 0.67% yeast nitrogen base, 0.5%casamino acids, 2% glucose, 10 μg/ml adenine and 20 μg/ml uracil. Hoststrains transformed by vectors comprising the ADH2 promoter may be grownfor expression in a rich medium consisting of 1% yeast extract, 2%peptone, and 1% glucose supplemented with 80 μg/ml adenine and 80 μg/mluracil. Derepression of the ADH2 promoter occurs upon exhaustion ofmedium glucose. Crude yeast supernatants are harvested by filtration andheld at 4° C. prior to further purification.

Various mammalian or insect cell culture systems can be employed toexpress recombinant protein. Baculovirus systems for production ofheterologous proteins in insect cells are reviewed by Luckow andSummers, Bio/Technology 6:47 (1988). Examples of suitable mammalian hostcell lines include the COS-7 lines of monkey kidney cells, described byGluzman (Cell 23:175, 1981), and other cell lines capable of expressingan appropriate vector including, for example, CV-1/EBNA (ATCC CRL10478), L cells, C127, 3T3, Chinese hamster ovary (CHO), HeLa and BHKcell lines. Mammalian expression vectors may comprise nontranscribedelements such as an origin of replication, a suitable promoter andenhancer linked to the gene to be expressed, and other 5' or 3' flankingnontranscribed sequences, and 5' or 3' nontranslated sequences, such asnecessary ribosome binding sites, a polyadenylation site, splice donorand acceptor sites, and transcriptional termination sequences.

Purification of Receptors for IL-17

Purified IL-17R, homologs, or analogs are prepared by culturing suitablehost/vector systems to express the recombinant translation products ofthe DNAs of the present invention, which are then purified from culturemedia or cell extracts. For example, supernatants from systems whichsecrete recombinant protein into culture media can be first concentratedusing a commercially available protein concentration filter, forexample, an Amicon or Millipore Pellicon ultrafiltration unit.

Following the concentration step, the concentrate can be applied to asuitable purification matrix. For example, a suitable affinity matrixcan comprise a counter structure protein or lectin or antibody moleculebound to a suitable support. Alternatively, an anion exchange resin canbe employed, for example, a matrix or substrate having pendantdiethylaminoethyl (DEAE) groups. The matrices can be acrylamide,agarose, dextran, cellulose or other types commonly employed in proteinpurification. Alternatively, a cation exchange step can be employed.Suitable cation exchangers include various insoluble matrices comprisingsulfopropyl or carboxymethyl groups. Sulfopropyl groups are preferred.Gel filtration chromatography also provides a means of purifying theinventive proteins.

Affinity chromatography is a particularly preferred method of purifyingIL-17R and homologs thereof. For example, a IL-17R expressed as a fusionprotein comprising an immunoglobulin Fc region can be purified usingProtein A or Protein G affinity chromatography. Moreover, a IL-17Rprotein comprising an oligomerizing zipper domain may be purified on aresin comprising an antibody specific to the oligomerizing zipperdomain. Monoclonal antibodies against the IL-17R protein may also beuseful in affinity chromatography purification, by utilizing methodsthat are well-known in the art. A ligand (i.e., IL-17 or HVS-13) mayalso be used to prepare an affinity matrix for affinity purification ofIL-17R.

Finally, one or more reversed-phase high performance liquidchromatography (RP-HPLC) steps employing hydrophobic RP-HPLC media,e.g., silica gel having pendant methyl or other aliphatic groups, can beemployed to further purify a IL-17R composition. Some or all of theforegoing purification steps, in various combinations, can also beemployed to provide a homogeneous recombinant protein.

Recombinant protein produced in bacterial culture is usually isolated byinitial extraction from cell pellets, followed by one or moreconcentration, salting-out, aqueous ion exchange or size exclusionchromatography steps. Finally, high performance liquid chromatography(HPLC) can be employed for final purification steps. Microbial cellsemployed in expression of recombinant viral protein can be disrupted byany convenient method, including freeze-thaw cycling, sonication,mechanical disruption, or use of cell lysing agents.

Fermentation of yeast which express the inventive protein as a secretedprotein greatly simplifies purification. Secreted recombinant proteinresulting from a large-scale fermentation can be purified by methodsanalogous to those disclosed by Urdal et al. (J. Chromatog. 296:171,1984). This reference describes two sequential, reversed-phase HPLCsteps for purification of recombinant human GM-CSF on a preparative HPLCcolumn.

Protein synthesized in recombinant culture is characterized by thepresence of cell components, including proteins, in amounts and of acharacter which depend upon the purification steps taken to recover theinventive protein from the culture. These components ordinarily will beof yeast, prokaryotic or non-human higher eukaryotic origin andpreferably are present in innocuous contaminant quantities, on the orderof less than about 1 percent by weight. Further, recombinant cellculture enables the production of the inventive proteins free of otherproteins which may be normally associated with the proteins as they arefound in nature in the species of origin.

Administration of IL-17R Compositions

The present invention provides methods of using therapeutic compositionscomprising an effective amount of a protein and a suitable diluent andcarrier, and methods for regulating an immune response. The use ofIL-17R or homologs in conjunction with soluble cytokine receptors orcytokines, or other immunoregulatory molecules is also contemplated.Moreover, DNA encoding soluble IL-17R will also be useful; a tissue ororgan to be transplanted can be transfected with the DNA by any methodknown in the art. The organ or tissue thus expresses soluble IL-17R,which acts in the localized area of the graft to suppress rejection ofthe graft. Similar methods comprising administering such DNA's to thesite of the graft will also show efficacy in ameliorating graftrejection.

For therapeutic use, purified protein is administered to a patient,preferably a human, for treatment in a manner appropriate to theindication. Thus, for example, IL-17R protein compositions administeredto regulate immune function can be given by bolus injection, continuousinfusion, sustained release from implants, or other suitable technique.Typically, a therapeutic agent will be administered in the form of acomposition comprising purified IL-17R, in conjunction withphysiologically acceptable carriers, excipients or diluents. Suchcarriers will be nontoxic to recipients at the dosages andconcentrations employed.

Ordinarily, the preparation of such protein compositions entailscombining the inventive protein with buffers, antioxidants such asascorbic acid, low molecular weight (less than about 10 residues)polypeptides, proteins, amino acids, carbohydrates including glucose,sucrose or dextrins, chelating agents such as EDTA, glutathione andother stabilizers and excipients. Neutral buffered saline or salinemixed with conspecific serum albumin are exemplary appropriate diluents.Preferably, product is formulated as a lyophilizate using appropriateexcipient solutions (e.g., sucrose) as diluents. Appropriate dosages canbe determined in trials. The amount and frequency of administration willdepend, of course, on such factors as the nature and severity of theindication being treated, the desired response, the condition of thepatient, and so forth.

Receptors for IL-17 (CTLA-8) can be administered for the purpose ofinhibiting T cell proliferation, or for inhibiting T cell activation.Soluble IL-17R are thus likely to be useful in preventing or treatingorgan or graft rejection, autoimmune disease, allergy or asthma. Theinventive receptor proteins will also be useful for prevention ortreatment of inflammatory disease in which activated T cells play arole. Similarly, HVS13 and homologs thereof stimulate B cellproliferation and immunoglobulin secretion; thus, receptors that bindHVS13 or CTLA-8 will be useful in vivo to inhibit B cell proliferationor immunoglobulin secretion. Receptors for CTLA-8 will also be useful toinhibit the binding of HVS13 or CTLA-8 to cells expressing IL-17R.

The following examples are offered by way of illustration, and not byway of limitation. Those skilled in the art will recognize thatvariations of the invention embodied in the examples can be made,especially in light of the teachings of the various references citedherein, the disclosures of which are incorporated by reference.

EXAMPLE 1

This example describes identification of cells that express a receptor(or counterstructure) for HVS13/mCTLA8. A chimeric protein (HVS13 typeII Fc) consisting of an Fc region of a human immunoglobulin (SEQ IDNO:4) followed by the amino acid 19 to 151 of HVS13 (SEQ ID NO:8) wasprepared. A murine CTLA8/Fc (mCTLA8/Fc) was constructed by fusing aminoacid 22 to 150 of mCTLA8 (SEQ ID NO:6) to the Fc region of human IgG1. Acontrol Fc protein was constructed by a similar method. The HVS13/Fc andmCTLA-8 proteins were expressed and used to identify cell sources byflow cytometry.

Cells (1×10⁶) were preincubated on ice for 30 minutes in 100 μl of FACSbuffer (PBS, 1% FCS and 0.1% NaN3) containing 2% normal goat serum and2% normal rabbit serum to block nonspecific binding. 100 μl of HVS13/Fc,mCTLA-8/Fc or control/Fc protein was added at 5 μg/ml and incubated onice for 30 min. After washing, the cells were stained with biotinlabeled anti human IgG (Fc specific) followed by PE-conjugatedstreptavidin (Becton Dickson & Co, Mountain View, Calif.) in 100 μl ofFACS buffer. Cells were then washed and analyzed using a FACScan (BectonDickinson). A minimum of 5,000 cells were analyzed for each sample. Morethan a dozen cell lines were screened and it was found that bothHVS13/Fc and mCTLA8/Fc fusion proteins bound specifically to the murinethymoma cell line EL4. These cells did not bind to the control/Fc fusionprotein.

EXAMPLE 2

This example describes cloning of the gene that encodes IL-17R. Afteridentification of a source for HVS13 counterstructure, an EL4 mammalianexpression library was screened by a slide-binding autoradiographicmethod (Gearing et al., EMBO J. 8:3667, 1989). CV1/EBNA cells weremaintained in Dulbecco's modified Eagle's medium (DMEM) containing 10%(v/v) fetal calf serum (FCS) at 37° C. in a humidified atmospherecontaining 10% CO2 and passaged twice weekly. Subconfluent CV1/EBNA cellmonolayers on fibronectin-treated chamber slides (Labtek) weretransfected by a chloroquine-mediated DEAE-dextran procedure withplasmid DNAs derived from pooled transformants (2,000 transformants perpool) of murine El4cDNA library.

The CV1/EBNA cells transfected with the murine EL4cDNA pools wereassayed for HVS13/Fc binding two days after transfection using ¹²⁵ I!labeled goat anti-human IgG binding and slide autoradiography.Transfected cell monolayers were washed with binding medium (RPMI 1640containing 1% bovine serum albumin and 50 mg/ml non-fat dry milk), thenincubated with 1 μg/ml of HVS13/Fc for one hour at room temperature.Cells were washed, incubated with ¹²⁵ I-labeled goat anti-human IgG (NewEngland nuclear, Cambridge, Mass.). Cells were washed twice with bindingmedium, three times with PBS, and fixed in PBS containing 2.5%gluteraldehyde for 30 minutes, washed twice more with PBS and air dried.The chamber slides were then dipped in Kodak GTNB-2 photographicemulsion and exposed for 3 days at 4° C. before developing.

Forty pools of approximately 2,000 cDNA each were transfected intoCV1/EBNA cells. Two pools of cDNA were found to confer binding toHVS13/Fc protein. These pools were broken down to pools of 100 cDNAs,and subsequently to individual clones. Two single cDNA clones wereisolated. These clones were transfected into CV1/EBNA to determinewhether the protein encoded thereby conferred binding to both HVS13/Fcand mCTLA8/Fc. Both HVS/Fc and mCTLA8/Fc bound to CV1/EBNA cellstransfected with the cloned cDNA, but not to cells transfected withempty vector. Control/Fc did not bind to either of them.

Sequencing of these clones found that they contained a 3.2 kb and 1.7 kbinsert derived from same mRNA. The 3.2 kb clone contained an openreading frame of 2595 bp surrounded by 120 bp at the 5' noncodingsequence and 573 bp of 3' noncoding sequence. There were no in-framestop codons upstream of the predicted initiator methionine, which ispreceded by a purine residue (guanine) at -3 position, the mostimportant indicator of a good translation initiation site (Kozak, Mol.Cell. Biol. 9:5134, 1989). It also has a guanine at +4 position, makingit an optimal for translation initiation. The open reading frame ispredicted to encode a type I transmembrane protein of 864 amino acids.The nucleotide and predicted amino acid sequence is shown in SEQ IDNOs:1 and 2.

Computer analysis indicated that the protein has an N-terminal signalpeptide with a cleavage site between amino acid 31 and 32. The signalpeptide is followed by a 291 amino acid extracellular domain, a 21 aminoacid transmembrane domain, and a 521 amino acid cytoplasmic tail. Thereare eight potential N-linked glycosylation sites in the extracellulardomain of the protein. The predicted molecular weight for this proteinis 97.8 kilodaltons with an estimated isoelectric point of 4.85.Comparison of both nucleotide and amino acid sequences with the GenBankor EMBL databases found no significant homology with known nucleotideand protein sequences.

In order to determine the cellular and tissue distribution of IL-17RmRNA, poly (A)⁺ RNA derived from various murine cell lines or tissueswas examined by Northern blot analysis using the IL-17R cDNA as a probe.Filters containing poly(A)⁺ RNA (2 μg per lane) from various tissueswere purchased from Clontech (Palo Alto, Calif.). Polyadenylated RNAfrom various cells or cell lines were isolated, fractionated (2 μg perlane) on a 1% agarose formaldehyde gel, blotted onto Hybond nylonmembrane (Amersham). Filters were probed with an anti-sense RNAriboprobe corresponding to the coding region of IL-17R cDNA.Hybridization was performed at 63° C. followed by three washings in0.2%×SSC, 0.1% SDS at 68° C. Blots were exposed for 8 to 48 hr at -70°C.

The IL-17R probe hybridized to a single species of mRNA of approximately3.7 kb in all tissues. Among the tissues examined, strong hybridizingsignals were observed in spleen and kidney. Moderate signals wereobserved in lung and liver, and weaker signals in brain, heart, skeletalmuscle and testes. Similar size mRNAs were detected in the followingcells and cell lines: fetal liver epithelial cells (D11), fibroblast(3T3), rat intestinal epithelial cells (1CE6), splenic B cells, musclecells (BB4), mast cells (H7), triple negative thymus cells (TN), pre-Bcells (70Z/3), T cell hybridoma (EL4); and T cell clones 7C2 and D10.All the cell lines tested were found to express IL-17R mRNA, suggestinga ubiquitous expression of IL-17R message.

EXAMPLE 3

This example describes construction of a construct to express a solubleIL-17R/Flag® protein referred to as IL-17R/Flag. IL-17R/Flag® contains aleader sequence, and the region of IL-17R from amino acid 1 to aminoacid 322 (SEQ ID NO:1), and the octapeptide referred to as Flag® (SEQ IDNO:3). The construct is prepared essentially as described for othersoluble constructs, by ligating a DNA fragment encoding amino acids 1through 322 of SEQ ID NO:1 (prepared as described in Example 4) into anappropriate expression vector which contains a suitable leader sequence.The resultant DNA construct is transfected into a suitable cell linesuch as the monkey kidney cell line CV-1/EBNA (ATCC CRL 10478).IL-17R/Flag® may be purified using a Flag® antibody affinity column, andanalyzed for biological activity using any of the methods describedherein.

EXAMPLE 4

This example describes construction of a IL-17R DNA construct to expressa IL-17R/Fc fusion protein. A soluble form of IL-17R fused to the Fcregion of human IgG1 was constructed in the mammalian expression vectorpDC409 in the following way: A pair of oligonucleotide primerscontaining a sense sequence and an antisense sequence of IL-17R weresynthesized. The sense primer contained a Sal I site at the 5' end ofthe cDNA and antisense primer contained a Bgl II site and contained theIL-17R truncated just before the transmembrane region and a stop codon.A 980 bp DNA fragment was amplified from IL-17R cDNA. The PCR productwas cut with Sal I and Bgl II and used in a three way ligation with afragment carrying the human IgG1 region cut with Bgl II and Not I into aplasmid (pDC409; see U.S. Ser. No. 08/235,397) previously cut with Sal Iand Not I. The encoded insert contained the nucleotides encoding theamino acid sequence of residues 1 to 322 of IL-17R (SEQ ID NO:1). Thesequence was confirmed by sequencing the whole region.

The IL-17R/Fc expression plasmids were transfected into CV-1/EBNA cells,and supernatants were collected for 1 week. The CTLA-8/Fc fusionproteins were purified on a protein A sepharose column (Pharmacia,Uppsala, Sweden) as described below. Protein concentration wasdetermined by an enzyme-linked immunoadsorbent assay specific for theconstant domain of human IgG1 and by BCA analysis (Pharmacia), andpurity was confirmed by SDS-polyacrylamide gel electrophoresis analysisfollowed by silver stain of the gel.

EXAMPLE 5

This example describes purification of IL-17R fusion proteins. IL-17R/Fcfusion protein is purified by conventional methods using Protein A orProtein G chromatography. Approximately one liter of culture supernatantcontaining IL-17R/Fc fusion protein is purified by filtering mammaliancell supernatants (e.g., in a 0.45 m filter) and applying filtrate to aprotein A/G antibody affinity column (Schleicher and Schuell, Keene,N.H.) at 4° C. at a flow rate of 80 ml/hr for a 1.5 cm×12.0 cm column.The column is washed with 0.5M NaCl in PBS until free protein is notdetected in the wash buffer. Finally, the column is washed with PBS.Bound fusion protein is eluted from the column with 25 mM citratebuffer, pH 2.8, and brought to pH 7 with 500 mM Hepes buffer, pH 9.1.

A IL-17R fusion protein comprising Flag® may also be detected and/orpurified using an antibody that binds Flag®, substantially as describedin Hopp et al., Bio/Technology 6:1204 (1988). Biological activity ismeasured by inhibition of CTLA-8 activity in any biological assay whichquantifies the co-stimulatory effect of CTLA-8, for example, asdescribed in the Examples herein.

EXAMPLE 6

This example illustrates the preparation of monoclonal antibodiesagainst IL-17R. Preparations of purified recombinant IL-17R, forexample, or transfected cells expressing high levels of IL-17R, areemployed to generate monoclonal antibodies against IL-17R usingconventional techniques, such as those disclosed in U.S. Pat. No.4,411,993. Such antibodies are likely to be useful in interfering withIL-17R binding to CTLA-8, as components of diagnostic or research assaysfor IL-17R, or in affinity purification of IL-17R.

To immunize rodents, IL-17R immunogen is emulsified in an adjuvant (suchas complete or incomplete Freund's adjuvant, alum, or another adjuvant,such as Ribi adjuvant R700 (Ribi, Hamilton, Mont.), and injected inamounts ranging from 10-100 μg subcutaneously into a selected rodent,for example, BALB/c mice or Lewis rats. Ten days to three weeks dayslater, the immunized animals are boosted with additional immunogen andperiodically boosted thereafter on a weekly, biweekly or every thirdweek immunization schedule. Serum samples are periodically taken byretro-orbital bleeding or tail-tip excision for testing by dot-blotassay (antibody sandwich), ELISA (enzyme-linked immunosorbent assay),immunoprecipitation, or other suitable assays, including FACS analysis.Following detection of an appropriate antibody titer, positive animalsare given an intravenous injection of antigen in saline. Three to fourdays later, the animals are sacrificed, splenocytes harvested, and fusedto a murine myeloma cell line (e.g., NS1 or preferably Ag 8.653 ATCC CRL1580!). Hybridoma cell lines generated by this procedure are plated inmultiple microtiter plates in a selective medium (for example, onecontaining hypoxanthine, aminopterin, and thymidine, or HAT) to inhibitproliferation of non-fused cells, myeloma-myeloma hybrids, andsplenocyte-splenocyte hybrids.

Hybridoma clones thus generated can be screened by ELISA for reactivitywith IL-17R, for example, by adaptations of the techniques disclosed byEngvall et al., Immunochem. 8:871 (1971) and in U.S. Pat. No. 4,703,004.A preferred screening technique is the antibody capture techniquedescribed by Beckman et al., J. Immunol. 144:4212 (1990). Positiveclones are then injected into the peritoneal cavities of syngeneicrodents to produce ascites containing high concentrations (>1 mg/ml) ofanti-IL-17R monoclonal antibody. The resulting monoclonal antibody canbe purified by ammonium sulfate precipitation followed by gel exclusionchromatography. Alternatively, affinity chromatography based uponbinding of antibody to protein A or protein G can also be used, as canaffinity chromatography based upon binding to IL-17R protein.

EXAMPLE 7

This example illustrates the ability of IL-17R to inhibit theproliferative response of T cells to mitogens. Lymphoid organs wereharvested aseptically and cell suspension was created. Splenic and lymphnode T cells were isolated from the cell suspension. The purity of theresulting splenic T cell preparations was routinely >95% CD3⁺ and <1%sIgM⁺. Purified murine splenic T cells (2×10⁵ /well) were cultured witheither 1% PHA or 1 μg/ml Con A, and a soluble IL-17R was titered intothe assay. Proliferation was determined after 3 days with the additionof 1 μCi ³ H!thymidine. Secretion of cytokines (Interleukin-2) wasdetermined for murine T cells cultured for 24 hr with 1 μg/ml of Con Ain the presence or absence of 10 μg/ml of IL-17R.Fc or in the presenceof a control Fc protein. IL-2 production was measured by ELISA andresults expressed as ng/ml IL-2 produced.

Soluble IL-17R/Fc significantly inhibited the mitogen-inducedproliferation of purified murine splenic T cells in a dose dependentmanner, while a control Fc had no effect on the murine T cellproliferation. Complete inhibition of mitogen induced proliferation wasobserved at a soluble IL-17R.Fc concentration of 10 μg/ml. Analysis ofIL-2 production by splenic T cells activated with Con A in the presenceor absence of IL-17R.Fc in the culture revealed that addition ofIL-17R.Fc to the T-cell culture inhibited IL-2 production to levels8-9-fold lower than those observed in cultures containing media alone ormedia plus a control Fc protein. Similar results were observed whenpurified human T cells were used.

EXAMPLE 8

This example presents the isolation of a DNA encoding human IL-17R bycross species hybridization. A human peripheral blood lymphocyte librarywas prepared and screened substantially as described in U.S. Ser. No.08/249,189, using murine IL-17R DNA under moderately high stringencyconditions. Several clones of varying length were obtained. Sequencingdata indicated that the human IL-17R was approximately 76% identical tomurine IL-17R at the nucleotide level. The nucleotide and predictedamino acid sequence of human IL-17R is shown in SEQ ID NOs:10 and 11. Aplasmid (pGEMBL) containing DNA encoding the human IL-17 receptor(referred to as pGEMBL-HuIL-17R) in E. coli DH10, was deposited with theAmerican Type Culture Collection, 12301 Parklawn Drive, Rockville, Md.20852-1776, USA, on Jun. 5, 1995, under the conditions of the BudapestTreaty, and assigned accession number 69834.

The human IL-17R shared many features with the murine IL-17 R. Computeranalysis indicated that the protein has an N-terminal signal peptidewith a cleavage site between amino acid 27 and 28. The signal peptide isfollowed by a 293 amino acid extracellular domain, a 21 amino acidtransmembrane domain, and a 525 amino acid cytoplasmic tail. SolubleIL-17R comprises the signal peptide and the extracellular domain(residues 1 to 320 of SEQ ID NO:1) or a fragment thereof. Alternatively,a different signal peptide can be substituted for the native signalpeptide. A Type I Fc fusion protein (wherein DNA encoding the Fc regionof an immunoglobulin molecule is fused to DNA encoding the IL-17Rimmediately before, and in place of, the DNA encoding the transmembraneregion of the IL-17R) was prepared, substantially as described inExample 4. A soluble hIL-17R protein can be also expressed substantiallyas described in Example 3, or by any other method of preparing andexpressing the extracellular domain of IL-17R or a fragment thereof.

EXAMPLE 9

This example presents the localization and fine mapping of the murineIL-17R gene. A panel of DNA samples from an interspecific cross that hasbeen characterized for over 900 genetic markers throughout the genomewas analyzed. The genetic markers included in this map span between 50and 80 centi-Morgans on each mouse autosome and the X chromosome (Chr)(Saunders and Seldin, Genomics 8:524, 1990; Watson et al., MammalianGenome 2:158, 1992).

Initially, DNA from the two parental mice C3H/HeJ-gld and (C3H/HeJ-gld xMus spretus) F1! were digested with various restriction endonucleasesand hybridized with the IL-17R cDNA probe to determine restrictionfragment length variants (RFLVs) to allow haplotype analyses.Informative Bgl1 RFLVs were detected: C3H/HeJ-gld, 10.0 kb; Mus spretus,7.8 kb and 2.2 kb). In each of the backcross mice either the C3H/HeJ-gldparental band or all three bands (both Mus spretus bands and a halfintensity C3H/HEJ-gld band) were observed indicating that a single locuswas detected.

Comparison of the haplotype distribution of the IL-17R RFLVs indicatedthat this gene cosegregated in 111 of the 114 meiotic events examinedwith the Raf1 gene locus on mouse Chr 6. The best gene order (Bishop,Genet. Epidemiol. 2:349, 1985)±the standard deviation (Green, InGenetics and Probability in Animal Breeding Experiments. E. Green, ed.;Macmillan, New York, pp.77-113, 1981) was: (centromere) Raf1-2.6 cM±1.5cM - IL-17R-2.5 cM±1.5 cM-Cd4.

EXAMPLE 10

This example demonstrates that soluble IL-17R suppresses rejection oforgan grafts in vivo. Hearts from neonatal C57BL/6 (H-2^(b)) mice (lessthan 24 hours old) were transplanted into the ear pinnae of adult BALB/c(H-2^(d)) recipients substantially as described in U.S. Pat. No.5,492,888, issued Feb. 20, 1996 (utilizing the method of Fulmer et al.,Am. J. Anat. 113:273, 1963, modified as described by Trager et al.,Transplantation 47:587, 1989, and Van Buren et al., Transplant. Proc.15:2967, 1983). Survival of the transplanted hearts was assessed byvisually inspecting the grafts for pulsatile activity, as determined byexamining the ear-heart grafts of anesthetized recipients under adissecting microscope with soft reflected light beginning on day 5 or 6post transplant. The time of graft rejection was defined as the dayafter transplantation on which contractile activity ceased.

In one set of experiments, neonatal hearts were removed, rinsed withsterile PBS to remove excess blood, and placed into prepared ear pinnae.Recipient mice were given either soluble murine IL-17R/Fc (100 μg in 200μl; see Example 4 herein) or rat IgG as a control, i.p. on days 0through 3 post transplantation. In a second set of experiments, therecipient mice were injected with IL-17R or human IgG on days 0, 1 and2; the quantity and route of injection were ass done previously. Theresults of these experiments are shown in Table 1.

                  TABLE 1    ______________________________________    Effects of Soluble Murine IL-17R (smuIL-17R) on    Neovascularized Heterotopic Cardiac Allograft Survival           Treatment                   Survival Time                              Median Survival Time ±           Group   (days)     S. D.    ______________________________________    Experiment 1             rat IgG   11, 14, 14, 14                                  13 ± 1.5             smuIL-17R 19, 19, 19, 21                                  20 ± 1.0    Experiment 2             human IgG 13, 13, 13, 15                                  14 ± 1.0             smuIL-17R 20, 20, 20, 20                                  20 ± 0.0    ______________________________________

Table 1 shows that heart allografts survived approximately 13 days inindividual control mice treated with rat IgG. When allograft recipientswere given up to four daily injections of soluble IL-17R, graft survivalwas prolonged, with a median survival of 20, approximately seven dayslonger than the survival time of identical grafts in control mice. Whena prolonged release of the IL-17R was obtained by encapsulating thesoluble IL-17R in alginate beads, it was observed that a singleadministration of 100 μg soluble IL-17R prolonged graft survival in muchthe same manner as observed previously with soluble IL-17R in solution.These results demonstrate that soluble IL-17R suppresses rejection ofgrafted tissues.

EXAMPLE 11

This example demonstrates that DNA encoding soluble IL-17R will beuseful in suppressing rejection of organ grafts in vivo. Hearts fromneonatal C57BL/6(H-2^(b)) mice were transplanted into the ear pinnae ofadult BALB/c (H-2^(d)) recipients as described in Example 10 above,except that the hearts were injected with 15 μl of PBS containing eitherIL-17R/Fc-encoding DNA (pDC409-IL-17R; Example 4) or control DNA (emptypDC409) at a concentration of about 1 mg/ml, into a ventricle. A 30gauge needle was used, and care was taken to minimize trauma to theheart. The transfected hearts were then transplanted into BALB/crecipients and graft survival determined as described previously.Results are presented below in Table 2.

                  TABLE 2    ______________________________________    Effects of Expression of Soluble Murine IL-17R by Cardiac Cells    on Neovascularized Heterotopic Cardiac Allograft Survival    Treatment                 Median Survival Time ±    Group      Survival Time (days)                              S. D.    ______________________________________    rat IgG    13, 15, 15, 15, 18                              15 ± 1.8    smuIL-17R  20, 25, 28, >60, >60                              ND*    ______________________________________     *ND: Not done; median survival time could not be calculated since two mic     still show pulsatile grafts more than two months after transplantation.

Table 2 shows that heart allografts survived approximately 15 days inindividual control mice transplanted with hearts transfected with emptyvector. When the transplanted hearts were transfected with DNA encodingsoluble IL-17R, graft survival was prolonged. For three of the five micein this group, grafts survived on average approximately 24 days, ninedays longer than the survival time of identical grafts in control mice.The grafts given the other two mice were still puslatile (i.e., had notbeen rejected) more than 60 days post transplant., and had apparentlybeen accepted by the recipients. These results demonstrate thattransfecting tissues to be grafted with DNA encoding soluble IL-17Rameliorates rejection of those tissues by the recipient.

    __________________________________________________________________________    SEQUENCE LISTING    (1) GENERAL INFORMATION:    (iii) NUMBER OF SEQUENCES: 10    (2) INFORMATION FOR SEQ ID NO:1:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 3288 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: single    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: cDNA to mRNA    (iii) HYPOTHETICAL: NO    (iv) ANTI-SENSE: NO    (vi) ORIGINAL SOURCE:    (A) ORGANISM: Mouse    (B) STRAIN: HVS13 receptor    (ix) FEATURE:    (A) NAME/KEY: CDS    (B) LOCATION: 121..2715    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:    GTCGACTGGAACGAGACGACCTGCTGCCGACGAGCGCCAGTCCTCGGCCGGGAAAGCCAT60    CGCGGGCCCTCGCTGTCGCGCGGAGCCAGCTGCGAGCGCTCCGCGACCGGGCCGAGGGCT120    ATGGCGATTCGGCGCTGCTGGCCACGGGTCGTCCCCGGGCCCGCGCTG168    MetAlaIleArgArgCysTrpProArgValValProGlyProAlaLeu    151015    GGATGGCTGCTTCTGCTGCTGAACGTTCTGGCCCCGGGCCGCGCCTCC216    GlyTrpLeuLeuLeuLeuLeuAsnValLeuAlaProGlyArgAlaSer    202530    CCGCGCCTCCTCGACTTCCCGGCTCCGGTCTGCGCGCAGGAGGGGCTG264    ProArgLeuLeuAspPheProAlaProValCysAlaGlnGluGlyLeu    354045    AGCTGCAGAGTCAAGAATAGTACTTGTCTGGATGACAGCTGGATCCAC312    SerCysArgValLysAsnSerThrCysLeuAspAspSerTrpIleHis    505560    CCCAAAAACCTGACCCCGTCTTCCCCAAAAAACATCTATATCAATCTT360    ProLysAsnLeuThrProSerSerProLysAsnIleTyrIleAsnLeu    65707580    AGTGTTTCCTCTACCCAGCACGGAGAATTAGTCCCTGTGTTGCATGTT408    SerValSerSerThrGlnHisGlyGluLeuValProValLeuHisVal    859095    GAGTGGACCCTGCAGACAGATGCCAGCATCCTGTACCTCGAGGGTGCA456    GluTrpThrLeuGlnThrAspAlaSerIleLeuTyrLeuGluGlyAla    100105110    GAGCTGTCCGTCCTGCAGCTGAACACCAATGAGCGGCTGTGTGTCAAG504    GluLeuSerValLeuGlnLeuAsnThrAsnGluArgLeuCysValLys    115120125    TTCCAGTTTCTGTCCATGCTGCAGCATCACCGTAAGCGGTGGCGGTTT552    PheGlnPheLeuSerMetLeuGlnHisHisArgLysArgTrpArgPhe    130135140    TCCTTCAGCCACTTTGTGGTAGATCCTGGCCAGGAGTATGAAGTGACT600    SerPheSerHisPheValValAspProGlyGlnGluTyrGluValThr    145150155160    GTTCACCACCTGCCGAAGCCCATCCCTGATGGGGACCCAAACCACAAA648    ValHisHisLeuProLysProIleProAspGlyAspProAsnHisLys    165170175    TCCAAGATCATCTTTGTGCCTGACTGTGAGGACAGCAAGATGAAGATG696    SerLysIleIlePheValProAspCysGluAspSerLysMetLysMet    180185190    ACTACCTCATGCGTGAGCTCAGGCAGCCTTTGGGATCCCAACATCACT744    ThrThrSerCysValSerSerGlySerLeuTrpAspProAsnIleThr    195200205    GTGGAGACCTTGGACACACAGCATCTGCGAGTGGACTTCACCCTGTGG792    ValGluThrLeuAspThrGlnHisLeuArgValAspPheThrLeuTrp    210215220    AATGAATCCACCCCCTACCAGGTCCTGCTGGAAAGTTTCTCCGACTCA840    AsnGluSerThrProTyrGlnValLeuLeuGluSerPheSerAspSer    225230235240    GAGAACCACAGCTGCTTTGATGTCGTTAAACAAATATTTGCGCCCAGG888    GluAsnHisSerCysPheAspValValLysGlnIlePheAlaProArg    245250255    CAAGAAGAATTCCATCAGCGAGCTAATGTCACATTCACTCTAAGCAAG936    GlnGluGluPheHisGlnArgAlaAsnValThrPheThrLeuSerLys    260265270    TTTCACTGGTGCTGCCATCACCACGTGCAGGTCCAGCCCTTCTTCAGC984    PheHisTrpCysCysHisHisHisValGlnValGlnProPhePheSer    275280285    AGCTGCCTAAATGACTGTTTGAGACACGCTGTGACTGTGCCCTGCCCA1032    SerCysLeuAsnAspCysLeuArgHisAlaValThrValProCysPro    290295300    GTAATCTCAAATACCACAGTTCCCAAGCCAGTTGCAGACTACATTCCC1080    ValIleSerAsnThrThrValProLysProValAlaAspTyrIlePro    305310315320    CTGTGGGTGTATGGCCTCATCACACTCATCGCCATTCTGCTGGTGGGA1128    LeuTrpValTyrGlyLeuIleThrLeuIleAlaIleLeuLeuValGly    325330335    TCTGTCATCGTGCTGATCATCTGTATGACCTGGAGGCTTTCTGGCGCC1176    SerValIleValLeuIleIleCysMetThrTrpArgLeuSerGlyAla    340345350    GATCAAGAGAAACATGGTGATGACTCCAAAATCAATGGCATCTTGCCC1224    AspGlnGluLysHisGlyAspAspSerLysIleAsnGlyIleLeuPro    355360365    GTAGCAGACCTGACTCCCCCACCCCTGAGGCCCAGGAAGGTCTGGATC1272    ValAlaAspLeuThrProProProLeuArgProArgLysValTrpIle    370375380    GTCTACTCGGCCGACCACCCCCTCTATGTGGAGGTGGTCCTAAAGTTC1320    ValTyrSerAlaAspHisProLeuTyrValGluValValLeuLysPhe    385390395400    GCCCAGTTCCTGATCACTGCCTGTGGCACTGAAGTAGCCCTTGACCTC1368    AlaGlnPheLeuIleThrAlaCysGlyThrGluValAlaLeuAspLeu    405410415    CTGGAAGAGCAGGTTATCTCTGAGGTGGGGGTCATGACCTGGGTGAGC1416    LeuGluGluGlnValIleSerGluValGlyValMetThrTrpValSer    420425430    CGACAGAAGCAGGAGATGGTGGAGAGCAACTCCAAAATCATCATCCTG1464    ArgGlnLysGlnGluMetValGluSerAsnSerLysIleIleIleLeu    435440445    TGTTCCCGAGGCACCCAAGCAAAGTGGAAAGCTATCTTGGGTTGGGCT1512    CysSerArgGlyThrGlnAlaLysTrpLysAlaIleLeuGlyTrpAla    450455460    GAGCCTGCTGTCCAGCTACGGTGTGACCACTGGAAGCCTGCTGGGGAC1560    GluProAlaValGlnLeuArgCysAspHisTrpLysProAlaGlyAsp    465470475480    CTTTTCACTGCAGCCATGAACATGATCCTGCCAGACTTCAAGAGGCCA1608    LeuPheThrAlaAlaMetAsnMetIleLeuProAspPheLysArgPro    485490495    GCCTGCTTCGGCACCTACGTTGTTTGCTACTTCAGTGGCATCTGTAGT1656    AlaCysPheGlyThrTyrValValCysTyrPheSerGlyIleCysSer    500505510    GAGAGGGATGTCCCCGACCTCTTCAACATCACCTCCAGGTACCCACTC1704    GluArgAspValProAspLeuPheAsnIleThrSerArgTyrProLeu    515520525    ATGGACAGATTTGAGGAGGTTTACTTCCGGATCCAGGACCTGGAGATG1752    MetAspArgPheGluGluValTyrPheArgIleGlnAspLeuGluMet    530535540    TTTGAACCCGGCCGGATGCACCATGTCAGAGAGCTCACAGGGGACAAT1800    PheGluProGlyArgMetHisHisValArgGluLeuThrGlyAspAsn    545550555560    TACCTGCAGAGCCCTAGTGGCCGGCAGCTCAAGGAGGCTGTGCTTAGG1848    TyrLeuGlnSerProSerGlyArgGlnLeuLysGluAlaValLeuArg    565570575    TTCCAGGAGTGGCAAACCCAGTGCCCCGACTGGTTCGAGCGTGAGAAC1896    PheGlnGluTrpGlnThrGlnCysProAspTrpPheGluArgGluAsn    580585590    CTCTGCTTAGCTGATGGCCAAGATCTTCCCTCCCTGGATGAAGAAGTG1944    LeuCysLeuAlaAspGlyGlnAspLeuProSerLeuAspGluGluVal    595600605    TTTGAAGACCCACTGCTGCCACCAGGGGGAGGAATTGTCAAACAGCAG1992    PheGluAspProLeuLeuProProGlyGlyGlyIleValLysGlnGln    610615620    CCCCTGGTGCGGGAACTCCCATCTGACGGCTGCCTTGTGGTAGATGTC2040    ProLeuValArgGluLeuProSerAspGlyCysLeuValValAspVal    625630635640    TGTGTCAGTGAGGAAGAAAGTAGAATGGCAAAGCTGGACCCTCAGCTA2088    CysValSerGluGluGluSerArgMetAlaLysLeuAspProGlnLeu    645650655    TGGCCACAGAGAGAGCTAGTGGCTCACACCCTCCAAAGCATGGTGCTG2136    TrpProGlnArgGluLeuValAlaHisThrLeuGlnSerMetValLeu    660665670    CCAGCAGAGCAGGTCCCTGCAGCTCATGTGGTGGAGCCTCTCCATCTC2184    ProAlaGluGlnValProAlaAlaHisValValGluProLeuHisLeu    675680685    CCAGACGGCAGTGGAGCAGCTGCCCAGCTGCCCATGACAGAGGACAGC2232    ProAspGlySerGlyAlaAlaAlaGlnLeuProMetThrGluAspSer    690695700    GAGGCTTGCCCGCTGCTGGGGGTCCAGAGGAACAGCATCCTTTGCCTC2280    GluAlaCysProLeuLeuGlyValGlnArgAsnSerIleLeuCysLeu    705710715720    CCCGTGGACTCAGATGACTTGCCACTCTGTAGCACCCCAATGATGTCA2328    ProValAspSerAspAspLeuProLeuCysSerThrProMetMetSer    725730735    CCTGACCACCTCCAAGGCGATGCAAGAGAGCAGCTAGAAAGCCTAATG2376    ProAspHisLeuGlnGlyAspAlaArgGluGlnLeuGluSerLeuMet    740745750    CTCTCGGTGCTGCAGCAGAGCCTGAGTGGACAGCCCCTGGAGAGCTGG2424    LeuSerValLeuGlnGlnSerLeuSerGlyGlnProLeuGluSerTrp    755760765    CCGAGGCCAGAGGTGGTCCTCGAGGGCTGCACACCCTCTGAGGAGGAG2472    ProArgProGluValValLeuGluGlyCysThrProSerGluGluGlu    770775780    CAGCGGCAGTCGGTGCAGTCGGACCAGGGCTACATCTCCAGGAGCTCC2520    GlnArgGlnSerValGlnSerAspGlnGlyTyrIleSerArgSerSer    785790795800    CCGCAGCCCCCCGAGTGGCTCACGGAGGAGGAAGAGCTAGAACTGGGT2568    ProGlnProProGluTrpLeuThrGluGluGluGluLeuGluLeuGly    805810815    GAGCCCGTTGAGTCTCTCTCTCCTGAGGAACTACGGAGCCTGAGGAAG2616    GluProValGluSerLeuSerProGluGluLeuArgSerLeuArgLys    820825830    CTCCAGAGGCAGCTTTTCTTCTGGGAGCTCGAGAAGAACCCTGGCTGG2664    LeuGlnArgGlnLeuPhePheTrpGluLeuGluLysAsnProGlyTrp    835840845    AACAGCTTGGAGCCACGGAGACCCACCCCAGAAGAGCAGAATCCCTCC2712    AsnSerLeuGluProArgArgProThrProGluGluGlnAsnProSer    850855860    TAGGCCTCCTGAGCCTGCTACTTAAGAGGGTGTATATTGTACTCTGTGTGTGC2765    865    GTGCGTGTGTGTGTGTGTGTGTGTGTGTGTGTGCGTGTGTGTGTGTGTGTGTGTGTGTGT2825    GTGTGTGTAGTGCCCGGCTTAGAAATGTGAACATCTGAATCTGACATAGTGTTGTATACC2885    TGAAGTCCCAGCACTTGGGAACTGAGACTTGATGATCTCCTGAAGCCAGGTGTTCAGGGC2945    CAGTGTGAAAACATAGCAAGACCTCAGAGAAATCAATGCAGACATCTTGGTACTGATCCC3005    TAAACACACCCCTTTCCCTGATAACCCGACATGAGCATCTGGTCATCATTGCACAAGAAT3065    CCACAGCCCGTTCCCAGAGCTCATAGCCAAGTGTGTTGCTCATTCCTTGAATATTTATTC3125    TGTACCTACTATTCATCAGACATTTGGAATTCAAAAACAAGTTACATGACACAGCCTTAG3185    CCACTAAGAAGCTTAAAATTCGGTAAGGATGTAAAATTAGCCAGGATGAATAGAGGGCTG3245    CTGCCCTGGCTGCAGAAGAGCAGGTCGTCTCGTTCCAGTCGAC3288    (2) INFORMATION FOR SEQ ID NO:2:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 864 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:    MetAlaIleArgArgCysTrpProArgValValProGlyProAlaLeu    151015    GlyTrpLeuLeuLeuLeuLeuAsnValLeuAlaProGlyArgAlaSer    202530    ProArgLeuLeuAspPheProAlaProValCysAlaGlnGluGlyLeu    354045    SerCysArgValLysAsnSerThrCysLeuAspAspSerTrpIleHis    505560    ProLysAsnLeuThrProSerSerProLysAsnIleTyrIleAsnLeu    65707580    SerValSerSerThrGlnHisGlyGluLeuValProValLeuHisVal    859095    GluTrpThrLeuGlnThrAspAlaSerIleLeuTyrLeuGluGlyAla    100105110    GluLeuSerValLeuGlnLeuAsnThrAsnGluArgLeuCysValLys    115120125    PheGlnPheLeuSerMetLeuGlnHisHisArgLysArgTrpArgPhe    130135140    SerPheSerHisPheValValAspProGlyGlnGluTyrGluValThr    145150155160    ValHisHisLeuProLysProIleProAspGlyAspProAsnHisLys    165170175    SerLysIleIlePheValProAspCysGluAspSerLysMetLysMet    180185190    ThrThrSerCysValSerSerGlySerLeuTrpAspProAsnIleThr    195200205    ValGluThrLeuAspThrGlnHisLeuArgValAspPheThrLeuTrp    210215220    AsnGluSerThrProTyrGlnValLeuLeuGluSerPheSerAspSer    225230235240    GluAsnHisSerCysPheAspValValLysGlnIlePheAlaProArg    245250255    GlnGluGluPheHisGlnArgAlaAsnValThrPheThrLeuSerLys    260265270    PheHisTrpCysCysHisHisHisValGlnValGlnProPhePheSer    275280285    SerCysLeuAsnAspCysLeuArgHisAlaValThrValProCysPro    290295300    ValIleSerAsnThrThrValProLysProValAlaAspTyrIlePro    305310315320    LeuTrpValTyrGlyLeuIleThrLeuIleAlaIleLeuLeuValGly    325330335    SerValIleValLeuIleIleCysMetThrTrpArgLeuSerGlyAla    340345350    AspGlnGluLysHisGlyAspAspSerLysIleAsnGlyIleLeuPro    355360365    ValAlaAspLeuThrProProProLeuArgProArgLysValTrpIle    370375380    ValTyrSerAlaAspHisProLeuTyrValGluValValLeuLysPhe    385390395400    AlaGlnPheLeuIleThrAlaCysGlyThrGluValAlaLeuAspLeu    405410415    LeuGluGluGlnValIleSerGluValGlyValMetThrTrpValSer    420425430    ArgGlnLysGlnGluMetValGluSerAsnSerLysIleIleIleLeu    435440445    CysSerArgGlyThrGlnAlaLysTrpLysAlaIleLeuGlyTrpAla    450455460    GluProAlaValGlnLeuArgCysAspHisTrpLysProAlaGlyAsp    465470475480    LeuPheThrAlaAlaMetAsnMetIleLeuProAspPheLysArgPro    485490495    AlaCysPheGlyThrTyrValValCysTyrPheSerGlyIleCysSer    500505510    GluArgAspValProAspLeuPheAsnIleThrSerArgTyrProLeu    515520525    MetAspArgPheGluGluValTyrPheArgIleGlnAspLeuGluMet    530535540    PheGluProGlyArgMetHisHisValArgGluLeuThrGlyAspAsn    545550555560    TyrLeuGlnSerProSerGlyArgGlnLeuLysGluAlaValLeuArg    565570575    PheGlnGluTrpGlnThrGlnCysProAspTrpPheGluArgGluAsn    580585590    LeuCysLeuAlaAspGlyGlnAspLeuProSerLeuAspGluGluVal    595600605    PheGluAspProLeuLeuProProGlyGlyGlyIleValLysGlnGln    610615620    ProLeuValArgGluLeuProSerAspGlyCysLeuValValAspVal    625630635640    CysValSerGluGluGluSerArgMetAlaLysLeuAspProGlnLeu    645650655    TrpProGlnArgGluLeuValAlaHisThrLeuGlnSerMetValLeu    660665670    ProAlaGluGlnValProAlaAlaHisValValGluProLeuHisLeu    675680685    ProAspGlySerGlyAlaAlaAlaGlnLeuProMetThrGluAspSer    690695700    GluAlaCysProLeuLeuGlyValGlnArgAsnSerIleLeuCysLeu    705710715720    ProValAspSerAspAspLeuProLeuCysSerThrProMetMetSer    725730735    ProAspHisLeuGlnGlyAspAlaArgGluGlnLeuGluSerLeuMet    740745750    LeuSerValLeuGlnGlnSerLeuSerGlyGlnProLeuGluSerTrp    755760765    ProArgProGluValValLeuGluGlyCysThrProSerGluGluGlu    770775780    GlnArgGlnSerValGlnSerAspGlnGlyTyrIleSerArgSerSer    785790795800    ProGlnProProGluTrpLeuThrGluGluGluGluLeuGluLeuGly    805810815    GluProValGluSerLeuSerProGluGluLeuArgSerLeuArgLys    820825830    LeuGlnArgGlnLeuPhePheTrpGluLeuGluLysAsnProGlyTrp    835840845    AsnSerLeuGluProArgArgProThrProGluGluGlnAsnProSer    850855860    *    865    (2) INFORMATION FOR SEQ ID NO:3:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 8 amino acids    (B) TYPE: amino acid    (C) STRANDEDNESS: Not Relevant    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: peptide    (vii) IMMEDIATE SOURCE:    (B) CLONE: FLAG.sub.-- peptide    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:    AspTyrLysAspAspAspAspLys    15    (2) INFORMATION FOR SEQ ID NO:4:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 212 amino acids    (B) TYPE: amino acid    (C) STRANDEDNESS: Not Relevant    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (vi) ORIGINAL SOURCE:    (A) ORGANISM: Human    (vii) IMMEDIATE SOURCE:    (B) CLONE: IgG1 Fc    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:    ArgSerCysAspLysThrHisThrCysProProCysProAlaProGlu    151015    LeuLeuGlyGlyProSerValPheLeuPheProProLysProLysAsp    202530    ThrLeuMetIleSerArgThrProGluValThrCysValValValAsp    354045    ValSerHisGluAspProGluValLysPheAsnTrpTyrValAspGly    505560    ValGluValHisAsnAlaLysThrLysProArgGluGluGlnTyrAsn    65707580    SerThrTyrArgValValSerValLeuThrValLeuHisGlnAspTrp    859095    LeuAsnGlyLysGluTyrLysCysLysValSerAsnLysAlaLeuPro    100105110    AlaProIleGluLysThrIleSerLysAlaLysGlyGlnProArgGlu    115120125    ProGlnValTyrThrLeuProProSerArgAspGluLeuThrLysAsn    130135140    GlnValSerLeuThrCysLeuValLysGlyPheTyrProSerAspIle    145150155160    AlaValGluTrpGluSerAsnGlyGlnProGluAsnAsnTyrLysThr    165170175    ThrProProValLeuAspSerAspGlySerPhePheLeuTyrSerLys    180185190    LeuThrValAspLysSerArgTrpGlnGlnGlyAsnValPheSerCys    195200205    SerValMetHis    210    (2) INFORMATION FOR SEQ ID NO:5:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 14 amino acids    (B) TYPE: amino acid    (C) STRANDEDNESS: Not Relevant    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: peptide    (vii) IMMEDIATE SOURCE:    (B) CLONE: Polylinker    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:    GlyGlyGlyGlySerGlyGlyGlyGlySerGlyGlyGlyGly    1510    (2) INFORMATION FOR SEQ ID NO:6:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 498 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: single    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: cDNA to mRNA    (iii) HYPOTHETICAL: NO    (iv) ANTI-SENSE: NO    (vi) ORIGINAL SOURCE:    (A) ORGANISM: Murine CTLA-8    (ix) FEATURE:    (A) NAME/KEY: CDS    (B) LOCATION: 14..490    (ix) FEATURE:    (A) NAME/KEY: sig.sub.-- peptide    (B) LOCATION: 14..88    (ix) FEATURE:    (A) NAME/KEY: mat.sub.-- peptide    (B) LOCATION: 89..487    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:    GTCGACCCCCACCATGTTCCATGTTTCTTTTAGATATATCTTTGGAATT49    MetPheHisValSerPheArgTyrIlePheGlyIle    25-20-15    CCTCCACTGATCCTTGTTCTGCTGCCTGTCACTAGTTCTGCGGTACTC97    ProProLeuIleLeuValLeuLeuProValThrSerSerAlaValLeu    10-51    ATCCCTCAAAGTTCAGCGTGTCCAAACACTGAGGCCAAGGACTTCCTC145    IleProGlnSerSerAlaCysProAsnThrGluAlaLysAspPheLeu    51015    CAGAATGTGAAGGTCAACCTCAAAGTCTTTAACTCCCTTGGCGCAAAA193    GlnAsnValLysValAsnLeuLysValPheAsnSerLeuGlyAlaLys    20253035    GTGAGCTCCAGAAGGCCCTCAGACTACCTCAACCGTTCCACGTCACCC241    ValSerSerArgArgProSerAspTyrLeuAsnArgSerThrSerPro    404550    TGGACTCTCCACCGCAATGAAGACCCTGATAGATATCCCTCTGTGATC289    TrpThrLeuHisArgAsnGluAspProAspArgTyrProSerValIle    556065    TGGGAAGCTCAGTGCCGCCACCAGCGCTGTGTCAATGCGGAGGGAAAG337    TrpGluAlaGlnCysArgHisGlnArgCysValAsnAlaGluGlyLys    707580    CTGGACCACCACATGAATTCTGTTCTCATCCAGCAAGAGATCCTGGTC385    LeuAspHisHisMetAsnSerValLeuIleGlnGlnGluIleLeuVal    859095    CTGAAGAGGGAGCCTGAGAGCTGCCCCTTCACTTTCAGGGTCGAGAAG433    LeuLysArgGluProGluSerCysProPheThrPheArgValGluLys    100105110115    ATGCTGGTGGGTGTGGGCTGCACCTGCGTGGCCTCGATTGTCCGCCAT481    MetLeuValGlyValGlyCysThrCysValAlaSerIleValArgHis    120125130    GCGTCCTAAGCGGCCGC498    AlaSer*    (2) INFORMATION FOR SEQ ID NO:7:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 158 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:    MetPheHisValSerPheArgTyrIlePheGlyIleProProLeuIle    25-20-15-10    LeuValLeuLeuProValThrSerSerAlaValLeuIleProGlnSer    515    SerAlaCysProAsnThrGluAlaLysAspPheLeuGlnAsnValLys    101520    ValAsnLeuLysValPheAsnSerLeuGlyAlaLysValSerSerArg    253035    ArgProSerAspTyrLeuAsnArgSerThrSerProTrpThrLeuHis    40455055    ArgAsnGluAspProAspArgTyrProSerValIleTrpGluAlaGln    606570    CysArgHisGlnArgCysValAsnAlaGluGlyLysLeuAspHisHis    758085    MetAsnSerValLeuIleGlnGlnGluIleLeuValLeuLysArgGlu    9095100    ProGluSerCysProPheThrPheArgValGluLysMetLeuValGly    105110115    ValGlyCysThrCysValAlaSerIleValArgHisAlaSer    120125130    (2) INFORMATION FOR SEQ ID NO:8:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 151 amino acids    (B) TYPE: amino acid    (C) STRANDEDNESS: Not Relevant    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (iii) HYPOTHETICAL: NO    (iv) ANTI-SENSE: NO    (vi) ORIGINAL SOURCE:    (A) ORGANISM: Herpesvirus Saimiri    (B) STRAIN: ORF13    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:8:    MetThrPheArgMetThrSerLeuValLeuLeuLeuLeuLeuSerIle    151015    AspCysIleValLysSerGluIleThrSerAlaGlnThrProArgCys    202530    LeuAlaAlaAsnAsnSerPheProArgSerValMetValThrLeuSer    354045    IleArgAsnTrpAsnThrSerSerLysArgAlaSerAspTyrTyrAsn    505560    ArgSerThrSerProTrpThrLeuHisArgAsnGluAspGlnAspArg    65707580    TyrProSerValIleTrpGluAlaLysCysArgTyrLeuGlyCysVal    859095    AsnAlaAspGlyAsnValAspTyrHisMetAsnSerValProIleGln    100105110    GlnGluIleLeuValValArgLysGlyHisGlnProCysProAsnSer    115120125    PheArgLeuGluLysMetLeuValThrValGlyCysThrCysValThr    130135140    ProIleValHisAsnValAsp    145150    (2) INFORMATION FOR SEQ ID NO:9:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 3223 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: single    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: cDNA to mRNA    (iii) HYPOTHETICAL: NO    (iv) ANTI-SENSE: NO    (vi) ORIGINAL SOURCE:    (A) ORGANISM: Human    (B) STRAIN: IL-17 R (hCTLA8 receptor)    (ix) FEATURE:    (A) NAME/KEY: CDS    (B) LOCATION: 93..2693    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:9:    GGGAGACCGGAATTCCGGGAAAAGAAAGCCTCAGAACGTTCGCTCGCTGCGTCCCCAGCC60    GGGGCCGAGCCCTCCGCGACGCCACCCGGGCCATGGGGGCCGCACGCAGCCCG113    MetGlyAlaAlaArgSerPro    15    CCGTCCGCTGTCCCGGGGCCCCTGCTGGGGCTGCTCCTGCTGCTCCTG161    ProSerAlaValProGlyProLeuLeuGlyLeuLeuLeuLeuLeuLeu    101520    GGCGTGCTGGCCCCGGGTGGCGCCTCCCTGCGACTCCTGGACCACCGG209    GlyValLeuAlaProGlyGlyAlaSerLeuArgLeuLeuAspHisArg    253035    GCGCTGGTCTGCTCCCAGCCGGGGCTAAACTGCACGGTCAAGAATAGT257    AlaLeuValCysSerGlnProGlyLeuAsnCysThrValLysAsnSer    40455055    ACCTGCCTGGATGACAGCTGGATTCACCCTCGAAACCTGACCCCCTCC305    ThrCysLeuAspAspSerTrpIleHisProArgAsnLeuThrProSer    606570    TCCCCAAAGGACCTGCAGATCCAGCTGCACTTTGCCCACACCCAACAA353    SerProLysAspLeuGlnIleGlnLeuHisPheAlaHisThrGlnGln    758085    GGAGACCTGTTCCCCGTGGCTCACATCGAATGGACACTGCAGACAGAC401    GlyAspLeuPheProValAlaHisIleGluTrpThrLeuGlnThrAsp    9095100    GCCAGCATCCTGTACCTCGAGGGTGCAGAGTTATCTGTCCTGCAGCTG449    AlaSerIleLeuTyrLeuGluGlyAlaGluLeuSerValLeuGlnLeu    105110115    AACACCAATGAACGTTTGTGCGTCAGGTTTGAGTTTCTGTCCAAACTG497    AsnThrAsnGluArgLeuCysValArgPheGluPheLeuSerLysLeu    120125130135    AGGCATCACCACAGGCGGTGGCGTTTTACCTTCAGCCACTTTGTGGTT545    ArgHisHisHisArgArgTrpArgPheThrPheSerHisPheValVal    140145150    GACCCTGACCAGGAATATGAGGTGACCGTTCACCACCTGCCCAAGCCC593    AspProAspGlnGluTyrGluValThrValHisHisLeuProLysPro    155160165    ATCCCTGATGGGGACCCAAACCACCAGTCCAAGAATTTCCTTGTGCCT641    IleProAspGlyAspProAsnHisGlnSerLysAsnPheLeuValPro    170175180    GACTGTGAGCACGCCAGGATGAAGGTAACCACGCCATGCATGAGCTCA689    AspCysGluHisAlaArgMetLysValThrThrProCysMetSerSer    185190195    GGCAGCCTGTGGGACCCCAACATCACCGTGGAGACCCTGGAGGCCCAC737    GlySerLeuTrpAspProAsnIleThrValGluThrLeuGluAlaHis    200205210215    CAGCTGCGTGTGAGCTTCACCCTGTGGAACGAATCTACCCATTACCAG785    GlnLeuArgValSerPheThrLeuTrpAsnGluSerThrHisTyrGln    220225230    ATCCTGCTGACCAGTTTTCCGCACATGGAGAACCACAGTTGCTTTGAG833    IleLeuLeuThrSerPheProHisMetGluAsnHisSerCysPheGlu    235240245    CACATGCACCACATACCTGCGCCCAGACCAGAAGAGTTCCACCAGCGA881    HisMetHisHisIleProAlaProArgProGluGluPheHisGlnArg    250255260    TCCAACGTCACACTCACTCTACGCAACCTTAAAGGGTGCTGTCGCCAC929    SerAsnValThrLeuThrLeuArgAsnLeuLysGlyCysCysArgHis    265270275    CAAGTGCAGATCCAGCCCTTCTTCAGCAGCTGCCTCAATGACTGCCTC977    GlnValGlnIleGlnProPhePheSerSerCysLeuAsnAspCysLeu    280285290295    AGACACTCCGCGACTGTTTCCTGCCCAGAAATGCCAGACACTCCAGAA1025    ArgHisSerAlaThrValSerCysProGluMetProAspThrProGlu    300305310    CCAATTCCGGACTACATGCCCCTGTGGGTGTACTGGTTCATCACGGGC1073    ProIleProAspTyrMetProLeuTrpValTyrTrpPheIleThrGly    315320325    ATCTCCATCCTGCTGGTGGGCTCCGTCATCCTGCTCATCGTCTGCATG1121    IleSerIleLeuLeuValGlySerValIleLeuLeuIleValCysMet    330335340    ACCTGGAGGCTAGCTGGGCCTGGAAGTGAAAAATACAGTGATGACACC1169    ThrTrpArgLeuAlaGlyProGlySerGluLysTyrSerAspAspThr    345350355    AAATACACCGATGGCCTGCCTGCGGCTGACCTGATCCCCCCACCGCTG1217    LysTyrThrAspGlyLeuProAlaAlaAspLeuIleProProProLeu    360365370375    AAGCCCAGGAAGGTCTGGATCATCTACTCAGCCGACCACCCCCTCTAC1265    LysProArgLysValTrpIleIleTyrSerAlaAspHisProLeuTyr    380385390    GTGGACGTGGTCCTGAAATTCGCCCAGTTCCTGCTCACCGCCTGCGGC1313    ValAspValValLeuLysPheAlaGlnPheLeuLeuThrAlaCysGly    395400405    ACGGAAGTGGCCCTGGACCTGCTGGAAGAGCAGGCCATCTCGGAGGCA1361    ThrGluValAlaLeuAspLeuLeuGluGluGlnAlaIleSerGluAla    410415420    GGAGTCATGACCTGGGTGGGCCGTCAGAAGCAGGAGATGGTGGAGAGC1409    GlyValMetThrTrpValGlyArgGlnLysGlnGluMetValGluSer    425430435    AACTCTAAGATCATCGTCCTGTGCTCCCGCGGCACGCGCGCCAAGTGG1457    AsnSerLysIleIleValLeuCysSerArgGlyThrArgAlaLysTrp    440445450455    CAGGCGCTCCTGGGCCGGGGGGCGCCTGTGCGGCTGCGCTGCGACCAC1505    GlnAlaLeuLeuGlyArgGlyAlaProValArgLeuArgCysAspHis    460465470    GGAAAGCCCGTGGGGGACCTGTTCACTGCAGCCATGAACATGATCCTC1553    GlyLysProValGlyAspLeuPheThrAlaAlaMetAsnMetIleLeu    475480485    CCGGACTTCAAGAGGCCAGCCTGCTTCGGCACCTACGTAGTCTGCTAC1601    ProAspPheLysArgProAlaCysPheGlyThrTyrValValCysTyr    490495500    TTCAGCGAGGTCAGCTGTGACGGCGACGTCCCCGACCTGTTCGGCGCG1649    PheSerGluValSerCysAspGlyAspValProAspLeuPheGlyAla    505510515    GCGCCGCGGTACCCGCTCATGGACAGGTTCGAGGAGGTGTACTTCCGC1697    AlaProArgTyrProLeuMetAspArgPheGluGluValTyrPheArg    520525530535    ATCCAGGACCTGGAGATGTTCCAGCCGGGCCGCATGCACCGCGTAGGG1745    IleGlnAspLeuGluMetPheGlnProGlyArgMetHisArgValGly    540545550    GAGCTGTCGGGGGACAACTACCTGCGGAGCCCGGGCGGCAGGCAGCTC1793    GluLeuSerGlyAspAsnTyrLeuArgSerProGlyGlyArgGlnLeu    555560565    CGCGCCGCCCTGGACAGGTTCCGGGACTGGCAGGTCCGCTGTCCCGAC1841    ArgAlaAlaLeuAspArgPheArgAspTrpGlnValArgCysProAsp    570575580    TGGTTCGAATGTGAGAACCTCTACTCAGCAGATGACCAGGATGCCCCG1889    TrpPheGluCysGluAsnLeuTyrSerAlaAspAspGlnAspAlaPro    585590595    TCCCTGGACGAAGAGGTGTTTGAGGAGCCACTGCTGCCTCCGGGAACC1937    SerLeuAspGluGluValPheGluGluProLeuLeuProProGlyThr    600605610615    GGCATCGTGAAGCGGGCGCCCCTGGTGCGCGAGCCTGGCTCCCAGGCC1985    GlyIleValLysArgAlaProLeuValArgGluProGlySerGlnAla    620625630    TGCCTGGCCATAGACCCGCTGGTCGGGGAGGAAGGAGGAGCAGCAGTG2033    CysLeuAlaIleAspProLeuValGlyGluGluGlyGlyAlaAlaVal    635640645    GCAAAGCTGGAACCTCACCTGCAGCCCCGGGGTCAGCCAGCGCCGCAG2081    AlaLysLeuGluProHisLeuGlnProArgGlyGlnProAlaProGln    650655660    CCCCTCCACACCCTGGTGCTCGCCGCAGAGGAGGGGGCCCTGGTGGCC2129    ProLeuHisThrLeuValLeuAlaAlaGluGluGlyAlaLeuValAla    665670675    GCGGTGGAGCCTGGGCCCCTGGCTGACGGTGCCGCAGTCCGGCTGGCA2177    AlaValGluProGlyProLeuAlaAspGlyAlaAlaValArgLeuAla    680685690695    CTGGCGGGGGAGGGCGAGGCCTGCCCGCTGCTGGGCAGCCCGGGCGCT2225    LeuAlaGlyGluGlyGluAlaCysProLeuLeuGlySerProGlyAla    700705710    GGGCGAAATAGCGTCCTCTTCCTCCCCGTGGACCCCGAGGACTCGCCC2273    GlyArgAsnSerValLeuPheLeuProValAspProGluAspSerPro    715720725    CTTGGCAGCAGCACCCCCATGGCGTCTCCTGACCTCCTTCCAGAGGAC2321    LeuGlySerSerThrProMetAlaSerProAspLeuLeuProGluAsp    730735740    GTGAGGGAGCACCTCGAAGGCTTGATGCTCTCGCTCTTCGAGCAGAGT2369    ValArgGluHisLeuGluGlyLeuMetLeuSerLeuPheGluGlnSer    745750755    CTGAGCTGCCAGGCCCAGGGGGGCTGCAGTAGACCCGCCATGGTCCTC2417    LeuSerCysGlnAlaGlnGlyGlyCysSerArgProAlaMetValLeu    760765770775    ACAGACCCACACACGCCCTACGAGGAGGAGCAGCGGCAGTCAGTGCAG2465    ThrAspProHisThrProTyrGluGluGluGlnArgGlnSerValGln    780785790    TCTGACCAGGGCTACATCTCCAGGAGCTCCCCGCAGCCCCCCGAGGGA2513    SerAspGlnGlyTyrIleSerArgSerSerProGlnProProGluGly    795800805    CTCACGGAAATGGAGGAAGAGGAGGAAGAGGAGCAGGACCCAGGGAAG2561    LeuThrGluMetGluGluGluGluGluGluGluGlnAspProGlyLys    810815820    CCGGCCCTGCCACTCTCTCCCGAGGACCTGGAGAGCCTGAGGAGCCTC2609    ProAlaLeuProLeuSerProGluAspLeuGluSerLeuArgSerLeu    825830835    CAGCGGCAGCTGCTTTTCCGCCAGCTGCAGAAGAACTCGGGCTGGGAC2657    GlnArgGlnLeuLeuPheArgGlnLeuGlnLysAsnSerGlyTrpAsp    840845850855    ACGATGGGGTCAGAGTCAGAGGGGCCCAGTGCATGAGGGCGGCTCC2703    ThrMetGlySerGluSerGluGlyProSerAla*    860865    CCAGGGACCGCCCAGATCCCAGCTTTGAGAGAGGAGTGTGTGTGCACGTATTCATCTGTG2763    TGTACATGTCTGCATGTGTATATGTTCGTGTGTGAAATGTAGGCTTTAAAATGTAAATGT2823    CTGGATTTTAATCCCAGGCATCCCTCCTAACTTTTCTTTGTGCAGCGGTCTGGTTATCGT2883    CTATCCCCAGGGGAATCCACACAGCCCGCTCCCAGGAGCTAATGGTAGAGCGTCCTTGAG2943    GCTCCATTATTCGTTCATTCAGCATTTATTGTGCACCTACTATGTGGCGGGCATTTGGGA3003    TACCAAGATAAATTGCATGCGGCATGGCCCCAGCCATGAAGGAACTTAACCGCTAGTGCC3063    GAGGACACGTTAAACGAACAGGATGGGCCGGGCACGGTGGCTCACGCCTGTAATCCCAGC3123    ACACTGGGAGGCCGAGGCAGGTGGATCACTCTGAGGTCAGGAGTTTGAGCCAGCCTGGCC3183    AACATGGTGAAACCCCGGAATTCGAGCTCGGTACCCGGGG3223    (2) INFORMATION FOR SEQ ID NO:10:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 866 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:10:    MetGlyAlaAlaArgSerProProSerAlaValProGlyProLeuLeu    151015    GlyLeuLeuLeuLeuLeuLeuGlyValLeuAlaProGlyGlyAlaSer    202530    LeuArgLeuLeuAspHisArgAlaLeuValCysSerGlnProGlyLeu    354045    AsnCysThrValLysAsnSerThrCysLeuAspAspSerTrpIleHis    505560    ProArgAsnLeuThrProSerSerProLysAspLeuGlnIleGlnLeu    65707580    HisPheAlaHisThrGlnGlnGlyAspLeuPheProValAlaHisIle    859095    GluTrpThrLeuGlnThrAspAlaSerIleLeuTyrLeuGluGlyAla    100105110    GluLeuSerValLeuGlnLeuAsnThrAsnGluArgLeuCysValArg    115120125    PheGluPheLeuSerLysLeuArgHisHisHisArgArgTrpArgPhe    130135140    ThrPheSerHisPheValValAspProAspGlnGluTyrGluValThr    145150155160    ValHisHisLeuProLysProIleProAspGlyAspProAsnHisGln    165170175    SerLysAsnPheLeuValProAspCysGluHisAlaArgMetLysVal    180185190    ThrThrProCysMetSerSerGlySerLeuTrpAspProAsnIleThr    195200205    ValGluThrLeuGluAlaHisGlnLeuArgValSerPheThrLeuTrp    210215220    AsnGluSerThrHisTyrGlnIleLeuLeuThrSerPheProHisMet    225230235240    GluAsnHisSerCysPheGluHisMetHisHisIleProAlaProArg    245250255    ProGluGluPheHisGlnArgSerAsnValThrLeuThrLeuArgAsn    260265270    LeuLysGlyCysCysArgHisGlnValGlnIleGlnProPhePheSer    275280285    SerCysLeuAsnAspCysLeuArgHisSerAlaThrValSerCysPro    290295300    GluMetProAspThrProGluProIleProAspTyrMetProLeuTrp    305310315320    ValTyrTrpPheIleThrGlyIleSerIleLeuLeuValGlySerVal    325330335    IleLeuLeuIleValCysMetThrTrpArgLeuAlaGlyProGlySer    340345350    GluLysTyrSerAspAspThrLysTyrThrAspGlyLeuProAlaAla    355360365    AspLeuIleProProProLeuLysProArgLysValTrpIleIleTyr    370375380    SerAlaAspHisProLeuTyrValAspValValLeuLysPheAlaGln    385390395400    PheLeuLeuThrAlaCysGlyThrGluValAlaLeuAspLeuLeuGlu    405410415    GluGlnAlaIleSerGluAlaGlyValMetThrTrpValGlyArgGln    420425430    LysGlnGluMetValGluSerAsnSerLysIleIleValLeuCysSer    435440445    ArgGlyThrArgAlaLysTrpGlnAlaLeuLeuGlyArgGlyAlaPro    450455460    ValArgLeuArgCysAspHisGlyLysProValGlyAspLeuPheThr    465470475480    AlaAlaMetAsnMetIleLeuProAspPheLysArgProAlaCysPhe    485490495    GlyThrTyrValValCysTyrPheSerGluValSerCysAspGlyAsp    500505510    ValProAspLeuPheGlyAlaAlaProArgTyrProLeuMetAspArg    515520525    PheGluGluValTyrPheArgIleGlnAspLeuGluMetPheGlnPro    530535540    GlyArgMetHisArgValGlyGluLeuSerGlyAspAsnTyrLeuArg    545550555560    SerProGlyGlyArgGlnLeuArgAlaAlaLeuAspArgPheArgAsp    565570575    TrpGlnValArgCysProAspTrpPheGluCysGluAsnLeuTyrSer    580585590    AlaAspAspGlnAspAlaProSerLeuAspGluGluValPheGluGlu    595600605    ProLeuLeuProProGlyThrGlyIleValLysArgAlaProLeuVal    610615620    ArgGluProGlySerGlnAlaCysLeuAlaIleAspProLeuValGly    625630635640    GluGluGlyGlyAlaAlaValAlaLysLeuGluProHisLeuGlnPro    645650655    ArgGlyGlnProAlaProGlnProLeuHisThrLeuValLeuAlaAla    660665670    GluGluGlyAlaLeuValAlaAlaValGluProGlyProLeuAlaAsp    675680685    GlyAlaAlaValArgLeuAlaLeuAlaGlyGluGlyGluAlaCysPro    690695700    LeuLeuGlySerProGlyAlaGlyArgAsnSerValLeuPheLeuPro    705710715720    ValAspProGluAspSerProLeuGlySerSerThrProMetAlaSer    725730735    ProAspLeuLeuProGluAspValArgGluHisLeuGluGlyLeuMet    740745750    LeuSerLeuPheGluGlnSerLeuSerCysGlnAlaGlnGlyGlyCys    755760765    SerArgProAlaMetValLeuThrAspProHisThrProTyrGluGlu    770775780    GluGlnArgGlnSerValGlnSerAspGlnGlyTyrIleSerArgSer    785790795800    SerProGlnProProGluGlyLeuThrGluMetGluGluGluGluGlu    805810815    GluGluGlnAspProGlyLysProAlaLeuProLeuSerProGluAsp    820825830    LeuGluSerLeuArgSerLeuGlnArgGlnLeuLeuPheArgGlnLeu    835840845    GlnLysAsnSerGlyTrpAspThrMetGlySerGluSerGluGlyPro    850855860    SerAla    865    __________________________________________________________________________

We claim:
 1. An isolated DNA selected from the group consisting of:(a) aDNA encoding a protein having an amino acid sequence of amino acids 1through 322 of SEQ ID NO.: 2; (b) a DNA encoding a protein having anamino acid sequence of amino acids 1 through 320 of SEQ ID NO.: 10; (c)DNA molecules capable of hybridization to the DNA of (a) or (b) understringent conditions, and which encode IL-17R that bind IL-17; and (d)fragments of the DNA molecules of (a), (b), or (c), which encodeproteins comprising an extracellular domain of the mature proteins ofSEQ ID NO:2 or SEQ ID NO:10, that bind L-17.
 2. An isolated DNA selectedfrom the group consisting of:(a) a DNA encoding a protein having anamino acid sequence of amino acids 1 through 322 of SEQ ID NO.: 2; and(b) a DNA encoding a protein having an amino acids sequence of aminoacids 1 through 320 of SEQ ID NO.:
 10. 3. An isolated DNA selected fromthe group consisting of:(a) a DNA encoding a protein having an aminoacid sequence of amino acids 1 through 322 of SEQ ID NO.: 2; (b) a DNAencoding a protein having an amino acid sequence of amino acids 1through 320 of SEQ ID NO.: 10; and (c) fragments of the DNA molecules of(a), or (b) which encode proteins comprising an extracellular domain ofthe mature proteins of SEQ ID NO:2 or SEQ ID NO:10, that bind IL-17. 4.A recombinant expression vector comprising a DNA sequence according toclaim
 1. 5. A recombinant expression vector according to claim 4 thatexpresses a soluble IL-17R.
 6. A recombinant expression vectorcomprising a DNA sequence according to claim
 3. 7. A host celltransformed or transfected with an expression vector according to claim4.
 8. A host cell transformed or transfected with an expression vectoraccording to claim
 5. 9. A host cell transformed or transfected with anexpression vector according to claim
 6. 10. A process for preparing anIL-17R protein, comprising culturing a host cell according to claim 7under conditions promoting expression and recovering the IL-17R.
 11. Aprocess for preparing an IL-17R protein, comprising culturing a hostcell according to claim 8 under conditions promoting expression andrecovering the IL-17R.
 12. A process for preparing an IL-17R protein,comprising culturing a host cell according to claim 9 under conditionspromoting expression and recovering the IL-17R.